Crazy inverted tricks on a ATCR250R! [Archive]

Red Rider

04-19-2006, 11:49 PM

Well the time has come for me to get inverted (forks, that is) as well. I've been wanting to do this since the CR's broke onto the scene with inverted forks back in 1990. I started getting serious about this project a little over a year ago. I measured several of the 250cc motocrosser's forks & quickly ruled them out because they were a tad too long. While I was at a Honda dealer, I measured a CR85's forks and quickly realized that they were the perfect length, but their 37mm diameter was a step down from my 250R's standard 39mm forks. I happened across a "Mini Rider" magazine that had a 85cc shootout, and that was when I saw the perfect set of forks, the KTM 85SX's. They're the perfect length once again, but their 43mm diameter is a step up compared to my stockers. I set up my eBay account to notify me of any 85SX forks for sale and then kept this new found "fork knowledge" to myself, as I didn't want any additional competition when it would come time to start the bidding. Well, I've never seen any of those forks on eBay yet, but all of the other 85's (KX, RM, YZ, & CR) come & go all the time. Then Billy (Honda ATC) let the cat out of the bag with his "Inverted fork ramblings" thread. He now posessed the same inverted fork knowledge that I did! He quickly acquired a set through the KTM Talk classifieds, and now his Z is "Rolling on inverts", as his thread was titled. I followed his lead and acquired a set the same way just after Christmas of last year. I finally got to start the conversion process a few weeks ago, and here's the progress so far.

Pic#1 shows the forks as they arrived, in a gun case no less. :)

Pic#2 compares the stock, standard fork to one of the USD's. The USD (Upside down) fork is shorter in total length than the stock fork, but when measured from the top to the front axle attach point, they're almost identical. As far as weight, each USD fork leg weighs almost a pound less!

Pics#3 & 4: I've got the spacing set & can start taking measurements for the triple clamps. Luckily, I was able to use the same fork spacing as the stock forks, 10 5/8" on center.

While Billy made all new triple clamps out of steel & changed the fork rake at the same time, I plan on keeping the fork rake the same while modifying my existing aluminum triple clamps. The only other option is to have completely new triple clamps machined, a la Speedbump and his ATCR250R conversion project.

Billy Golightly

04-20-2006, 12:13 AM

Welcome to the club!

That is something else that you were thinking about the KTM forks before and around the same time as me. Looks like it wasnt such a bad idea afterall if we both came up with it on our own :)

I remember you asking me in the one thread what the weight difference was, I was pretty sure they were lighter but I'm glad you ended up weighing them. Thats a considerible difference considering their bigger and stronger in every way.

Whats your theory on the tripples? Cut off the existing 250R fork mounting holes and weld on new ones that fit the KTM forks? I had considered that before I started making mine. Interested in seeing how it turns out. Keep us updated

69HemiGTX

04-20-2006, 01:20 AM

Sweet RR! I remember seeing an ATC250R at the dunes a few years ago with CR80 forks on it. It sure looked good and the owner said they were light years ahead of the stockers.

Red Rider

04-20-2006, 01:55 AM

Welcome to the club!Thanks Billy, although I won't actually be a card carrying club member until it's rideable. :(

Whats your theory on the tripples? Cut off the existing 250R fork mounting holes and weld on new ones that fit the KTM forks?Exactly. I only got the forks. No axle, fork guards, triple clamps, or front brake came with them. Even if the triple clamps did come with them, I wouldn't have used them, as they're pretty puny. I had some 49 & 53mm holes milled in a block 1 1/2" thick aluminum that I'll cut up & have welded onto my triple clamps.

Billy Golightly

04-20-2006, 06:47 AM

What kept me from doing it like that was the fact that in order to cut the stock clamps, and weld the new ones on there was going to have to be a heck of a lot of beveling and angle cutting to make enough room for the weld to penetrate and stack up. I didn't have any real way to do that since I dont have a vertical band saw. If you can pull it off this way though you'll sure have saved yourself alot of head ache. I'm getting ready to start on my second set in aluminum. Just bought the 3/8 6061 last night :)

I was going to ask you about the brake. Any ideas on that yet? The stock 85SX caliper is useless, way to small for anything but a mountain bike.

Also, FYI KTM105SX front forks are exactly the same as the 85s. KTM 200MXC front forks are the same diameter but are longer. Seals, ect are the same. Dont know about the internals. Just a little tidbit incase you decide to make another set or someone else does :)

If you have trouble finding a set of springs try finding some for the 200MXC. When I got mine from Moto Pro I only had a few hours to put them in or I wasnt riding. The springs because they were a larger diameter winding made the ID of the springs smaller. Cant increase the OD of them or it wouldn't fit in the tubes, so they wound inward and it caused some problems. Thats where the fork bladder rides at and sadly the springs wouldn't even fit over it. I had to grind it down for the fork to make it over it and not drag. I also trimmed some off of the end of each spring and them fit the length as they were off of a fullsize. They ended up being plenty stiff even without any revalving.

Darius1502

04-20-2006, 12:11 PM

Congrads...RedRider...

That R of yours has been begging for inverts!!

Love your 1989 R...always have!! Please show us tons of pics!!

Red Rider

04-20-2006, 01:53 PM

I remember you asking me in the one thread what the weight difference was, I was pretty sure they were lighter but I'm glad you ended up weighing them. Thats a considerible difference considering their bigger and stronger in every way.Whenever I change or modify something on my bike, I always try and weigh the before & after product. If I'm gonna change it, it better be lighter when I'm done! It's been pretty easy making things lighter, since most of the stuff that I changed was originally steel, and now it's aluminum, but I was worried that the inverted forks would be heavier, so I was pretty happy when they wound up weighing less.

I was going to ask you about the brake. Any ideas on that yet? The stock 85SX caliper is useless, way to small for anything but a mountain bike.Actually, my stock caliper matches right up with the mounting holes on the forks. The pads are nowhere near the disc, but it bolts right up! :w00t: Obviously, I'll have to sort that out later. I am hoping to use the stock caliper and just change the mounting bracket, but first I need to get the forks mounted up.

Darius, I know what you mean about the bike screaming for inverts. I'm going to miss the red fork boots though. Do you think I should retain the fork boots, and just slide them down to the bottom? :rolleyes:

Mr. Sandman

04-20-2006, 02:41 PM

It's about time you broke this news Red. My lip is raw from chewing on it to keep the big secret ever since I found out that you were doing this. Hurry up and get it done so I can see/try/ride the final product. Then I'll find some new legs for my R and you can start building another set, only better, and without the bugs.

Thanks for the news on the other KTMs Billy. Knowing this will help me to find a set of USD's much easier. :w00t:

Jeb

04-20-2006, 04:57 PM

...Do you think I should retain the fork boots, and just slide them down to the bottom? :rolleyes:

Stretch 'em out over the upper portion! So they look normal. :lol:

Those KTM 85SX forks look like just about the perfect USD 3-wheeler fork. I bet they would improve the 84 or 85 KXT250 immensly. Tecate's are leading-axle anyway. BigGreenMachine, oughta grab some and slap on your 85! :w00t:

This has got me day-dreaming of resurrecting my 84 KXT with a set of those forks up front. Sadly, about all I have left of it is the frame and an 85 front wheel assembly. :( :beer

More than enough to start a restoration! :p

OZQUAD44

04-21-2006, 11:41 AM

Jeb, could you post some more pictures of your "big three" Tecate, Tri-z, 250r

Ive got the rarest of the three, and one day I'd like to have the other two.

I Needs some motivational snaps

Cheers

Jeb

04-21-2006, 02:07 PM

Jeb, could you post some more pictures of your "big three" Tecate, Tri-z, 250r

Ive got the rarest of the three, and one day I'd like to have the other two.

I Needs some motivational snaps

Cheers

Hi OZQUAD! Maybe this evening I can get some up.

Thanks! :beer

BigGreenMachine

04-21-2006, 02:27 PM

Very nice mod to any trike these days as the conventional forks are dated in design.

Jeb, would love to put some USD's on my fat tired machine but the cash flow won't allow.

James

Red Rider

04-24-2006, 01:44 AM

Well, I made a little more progress my last few days off. I've been building a jig that will hold everything nice & straight (I hope) while the ends are welded back onto the triple clamps. It was going along smoothly, and as always, I ran into a setback (read as: I made a mistake!) that really slowed me down and required redoing some work that was already done.

The pics show the almost completed jig with the forks in place. I'm going to have only one side welded up at a time. That's why one of the original forks is mounted up in the jig alongside the USD fork. This will help hold the triple clamps straight, while the jig holds the forks straight & parallel. Once the one side is welded, I'll reset the fork guides on the jig to accept the other USD fork, and then have that side welded as well. In the final pic, you can clearly see that I'm passed the point of no return with the triple clamps, as I've already cut the ends off of the left side. That was scary. :eek:

The jig is made out of 3/4" partical board, and is reinforced on the backside with 1/4" thick 2" x 2" angle steel. All of the forks guides are made out of the same angle steel. It's all very stout & should work as planned. Before anybody asks, gravity & a tight fit is holding the forks in place right now, but they will be clamped to the jig as well, when welded.

Billy, thanks for the additional spring & miscellaneous info. Also, you mentioned that you'd purchased some 3/8" thick aluminum for a set of aluminum triple clamps. Are you going to make those the same way that you did the original steel ones?

Sandman, thanks for keeping the news under your hat. I hope your lip heals soon.

Billy Golightly

04-24-2006, 11:54 AM

Jig is looking good so far! Just becareful that when it goes to weld that you dont burn a hole in the wood :D Been there done that. Do you have the KTM clamps where your going to cut those ends off, or are you making all new pieces to weld on? Hows your front fender gonna fit using the original mounts? Mine is kind of a tight fit because the notches in the fender for the forks/fork boots werent big enough for the KTM forks. I kind of had to mount it at a funny angle for it to fit in there.

On my aluminum ones, Yup, pretty much. Going to keep a 3/8 thickness on most everything. The problem I'm having right now is locating a good source of the rubber handlebar clamp antivibe pieces. I need to have those so that I can have Ronnie (Yamahondaman) turn out some of the weld in pieces that they (the dampners) will sit in on a CNC lathe, that way the taper is perfect and the handlebars wont have any slack. Thats the main problem with my steelies right now. We used a custom made tapered drill bit and it didn't come out to good.

I think I'm seeing things, but have the bar mounts on your top tripple been cut off and re-welded closer together and solid? Just looking at the underside of it in the one picture it looks like there was a place where the antivibe rubbers and stuff would have sat but its like a round welded up circle now? I cant remember if the 250R clamps were a solid mount or not originally, Must be going crazy.

Red Rider

04-24-2006, 02:11 PM

I think I'm seeing things, but have the bar mounts on your top tripple been cut off and re-welded closer together and solid? Just looking at the underside of it in the one picture it looks like there was a place where the antivibe rubbers and stuff would have sat but its like a round welded up circle now? I cant remember if the 250R clamps were a solid mount or not originally, Must be going crazy.
Good eye there Billy! Yes, the 250R has solid-mount handlebar clamps, and mine are still solid-mounted, but they are closer together as you thought. You're not going crazy, yet. A few years ago, I decided to switch over to some Magura X-Line bulge bars, and I didn't want to use those fatbar adapter clamps that bolt onto the original handlebar clamps, so I cut off the old clamps & had some billet fatbar clamps welded on. The original clamp spacing was too wide for the fatbars, so I had to move them closer together, which opened up a hole on each side of the handlebar clamps.

The fender, like the front brake, will have to wait until the triple clamps are done, but now that you've asked, I'm curious also. Thanks for the fire warning. I'll be sure and keep a fire extinguisher handy while they're being welded. As Fire Marshall Bill used to say, "Everybody remain calm! I am a fire marshall!"

Billy Golightly

04-24-2006, 06:18 PM

Ahhh, now it makes sense! :) I did the same thing on my steel ones. I moved the clamps in to be the same width as dirtbike ones, that way I could run dirtbike bars with the narrow mounting area.

SpeedBump

04-24-2006, 06:59 PM

Super Conversion so far. I have run into the same issue with my handlebar mounts. I have a pair of 6061 billet blocks (3"x2"x11/5") for a new set of risers. I had to make new ones due to the fact the fork tubes will be protruding out the top of the clamps by more than 1 1/2". The stockers are too low (and they don't look TRICK either!)

Keep up the good work, should make a heck of a difference in ride and handling.

Red Rider

05-03-2006, 12:19 AM

I made a little more progress the past couple of days. Much of it has been slow tedious work. I got the top & bottom (left side) fork clamps cut out. I was taking it slow & easy while perfecting my methods. The right side should go a lot faster, now that I've got the technique down. Now that they're cut out, I need to do a lot of cutting, trimming & grinding on them and the triple clamps, so they'll fit together nicely before being welded.

Red Rider

06-17-2006, 02:52 AM

Well, I finally got a decent amount of work done on the triple clamps the past few days. Working on them a few hours here & there just hasn't been cutting it, not to mention that I was having a hard time getting motivated to work on this project, considering all of the tedious work that lay ahead of me. Well, that's all in the past now, as I'm finally ready for the welder. The left side will be welded first, then I'll cut the ends off the right side of the triple clamps, do some cutting & grinding to fine tune the fit of the new triple clamp ends, and then have that side welded as well. The first welding will be done this Monday. Wish me luck!

3WheelsOva4

06-17-2006, 07:38 AM

Looks good your 250 R is one of the best ive seen. Still..

RideRed250R

06-18-2006, 12:34 AM

my question is... if the stockers are 39mm and these are only 43mm 4mm difference, I would think, that 4mm taken out of the stock trees would still be stronger and cleaner then pre fabbed...
Adam

Red Rider

06-18-2006, 02:35 AM

Good thought. Unfortunately, the 43mm portion of the forks is on the slider portion of the forks, down where the front axle is. The upper portion of the forklegs, where they go through the triple clamps, is 49mm at the top clamp & 53mm at the bottom clamp.

Billy Golightly

06-18-2006, 11:23 AM

Those are looking good Red Rider. Interested in seeing how they turn out. I hope to get my welding torch repaired this week and then Ican finish up with my aluminum pair I had started making.

Red Rider

06-20-2006, 02:20 AM

Thanks 3w/4 & Billy. One leg down, one to go! So far, the welding has gone great. The jig seems to be working nicely, keeping everything in line as I'd hoped it would. In the pic, I've already ground down the external welds on the left side of both triple clamps, and the right side is all mounted up & ready for welding tomorrow. I only hope the right side comes out as good as the left. If all goes according to plans, it should be up on it's own 3 wheels tomorrow, sporting a sexy set of new legs!

Derrick Adams

06-20-2006, 04:36 AM

Looks really good so far. I hope your fender fits in there. Definately a trike to envy when it's done.
I'm watching this thread closely, as the inverted front is on my list of things to do this winter. I'm still wondering what forks to go with. I guess my determining factor will be how much trouble you have to go thru to get the right springs in there.
I'm still looking into the CR250 front fork swap, just modding them internally to lower the bike.

Keep up the good work. Seeing 2 trikes rolling on the same inverted fork set-up definately gets me amped to get a set!

Red Rider

06-21-2006, 03:17 AM

Thanks Derrick, the front fender fits with no problems or trimming whatsoever. I got the right side welded today, and everything is looking pretty good. Once again, I've ground down all of the external welds and have the triple clamps in their final shape. Now, I just need to do some sanding, sanding, and sanding. Oh yeah, I almost forgot, I'll need to do some sanding also. Then I'll polish them. I still need to get some stiffer springs, as well as get the front brake caliper mount figured out. :D

Billy Golightly

06-21-2006, 08:13 AM

Wow that came out really awesome! I was very concerned about how it was going to look but its real good. Turning radius still OK and not to short? They look very nice on your R too. How soft are they with the stock springs? I never even put mine on with the stock springs, so I dont know how it felt.

Red Rider

06-21-2006, 02:29 PM

Billy, there's a lot more sag in them with the stock springs than my original forks had. Right now they feel a bit harsh & I can hear the springs working around inside the fork legs when I bounce up & down on it, but there is very little oil inside the fork legs right now, so I'm pretty sure thats what is causing the harshness. When I built the triple clamps, I moved the forks 1/4" forward to compensate for their increased diameter up top because I didn't want to lose any turning radius. I have just as much turning radius now, as I did before. In fact, I plan on grinding the stops a little bit, to get a little more.

Dammit!

06-21-2006, 03:34 PM

I think it would look a bit better if you angled the front fender up a little to match the tire. Shouldn't be hard to do at all.

Looking forward to hearing how they perform out at the dunes. I was impressed how much difference it made when I just put some 2 inch spacers in my stockers. Inverts have to be pretty sweet once they're all dialed in.

hrc85250r

06-21-2006, 04:20 PM

at this point you have 3/4 ATC and 1/4 CR. its a real comfy dirtbike with two wheels in the back!

Louis Mielke

06-21-2006, 05:45 PM

at this point you have 3/4 ATC and 1/4 CR. its a real comfy dirtbike with two wheels in the back!

ummm ok.....whats your point? This post reads like a cut, am I missing something? His bike is awsome.

Red Rider

06-21-2006, 06:26 PM

I think it would look a bit better if you angled the front fender up a little to match the tire. Shouldn't be hard to do at all.That was the first thing I noticed after I got the front end all mounted up. The look is kind of reminiscent of the 86-87 Tecates, whose front fender seemed a bit low in the front, and I like the way the Tecates look. I'll try lowering the rear a tad & see how I like it.

Louis, I think HRC's post is referring to the fact that I call my ATC an ATCR250R, and I've been doing that ever since I first installed the CR250 cylinder on my bike, many, many years ago. Granted, my bike will never have as much CR in it as Speedbumps awesome conversion, but I think I've got the right amount. Thanks for sticking up for the bike though! :beer

Louis Mielke

06-21-2006, 06:33 PM

AH!! Now i get it. Totally forgot your bike was custom powervalved! Sorry HRC. I now have the missing peice!

Derrick Adams

06-21-2006, 06:42 PM

I'm kind of curious why you went with leading axle vs. the original trailing axle?

Billy Golightly

06-21-2006, 06:50 PM

I'm kind of curious why you went with leading axle vs. the original trailing axle?

The 85SX forks are leading axle originally ;)

Red Rider

06-22-2006, 02:06 AM

Derrick, as Billy said, the 85SX forks are already leading axle. I've never seen a pair of inverted forks that were designed to be trailing axle. If I spun them around to make them trailing axle, then the brake caliper would be out front, and that just wouldn't look quite right. If I have handling issues, then I may consider trying the trailing axle setup, or as a last resort, returning to the original forks. In hindsight, maybe I should have spun my original forks around to test the leading axle handling traits before I spent all this money, time & effort. Oh well, live & learn!

Red Rider

06-25-2006, 03:18 AM

Here are some before & after pics of the completed triple clamps.
Pics #1-2 were taken after smoothing out the external welds, but prior to polishing.

Pics #3-5 were taken after a days worth of sanding & polishing. I've noticed a few slightly dull spots that I may or may not go over again, as I'm so tired of the polishing process right now. The last pic shows the underside of both triple clamps. You can get a pretty good idea of the amount of welding that was done to them in this one.

Darius1502

06-25-2006, 12:13 PM

Redrider,

Incredible work. It looks like you are using the CR fork guards on the KTM forks. I heard that was possible..is this what I am seeing in the first pics?

Dammit!

06-25-2006, 12:13 PM

That looks awesome man. Good job!

SpeedBump

06-25-2006, 12:18 PM

I'm Impressed! Great looking clamps. Once mounted up, it would be hard to tell you BUILT from stockers. Nice.

Red Rider

06-25-2006, 04:22 PM

Thanks for all the compliments everyone!

It looks like you are using the CR fork guards on the KTM forks. I heard that was possible..is this what I am seeing in the first pics?Actually they are UFO replica fork guards for an 04-06' RM 250 that have been trimmed a little bit. The lower, front holes lined right up, but I had to drill new holes for the lower, side mounts. The CR 85 fork guards looked like they'd bolt right up, but I just don't care for the looks of them. For months, I was searching for a set of red fork guards (that would match my fenders & tank), and I thought I'd found some. They were made by Acerbis for a 99-03' RM 250 in "Diablo red", which was very close in color, but they were discontinued by Acerbis quite awhile ago. I'll see how I like the white ones. I may end up designing some red decals to get rid of some of that white down there.

Red Rider

07-30-2006, 10:40 PM

I finally finished up the inverted fork project! Well, almost finished up. Some of you might notice it's missing a front brake line. The fact that the caliper mounts a few inches lower than the stock setup, plus the way I have the line routed, all add up to needing a new, longer, stainless steel brake line. I got a set of 40kg. springs from Moto Pro Suspension to stiffen up the front end. John at Moto Pro was a great help determining the proper weight springs to get. This was the same company that Billy went through, when he did the inverted forks on his Tri-Z. This project was a lot easier to do since Billy had already paved the way, especially on the fork springs & the brake caliper.

Thanks again Billy!

Even though Billy did a Tri-Z & I did a 250R. It was comforting knowing that someone else came up with the same ideas to fix the front axle issues.

Billy Golightly

07-30-2006, 11:27 PM

Oh man...now thats the way ALL the 250Rs should have came like! Thats hella good looking. Matches the rest of your trike to a T. It looks like you mounted your caliper a little different ( and used the original mounting holes in that plate?). Mines only using about half the pad surface as the Z caliper but its still got enough grip to make you do a stoppy in the dirt :lol: Awesome conversion with the KTM forks...glad I was able to get somethign started with that. Maybe I'll be able to provide some tripples to folks interested in doing the same swap soon.

BTW, your fork seals will probably not be long for this world. Mine are already leaking and from what Iv'e read at KTM talk the OEM seals are known to be pretty junky. Supposedly a company called "Synergy" has high quality replacements.

Louis Mielke

07-30-2006, 11:44 PM

hmmmmm good to know billy. heh.

Red Rider

07-31-2006, 01:10 AM

Oh man...now thats the way ALL the 250Rs should have came like! Thats hella good looking. If Honda had built them like this originally, then mine would just be a really, really, really good looking ordinary 250R. The fact that Honda didn't do it makes it all that more special. I'm sure they would have done it in 1989 though? One can only wonder.

It looks like you mounted your caliper a little different ( and used the original mounting holes in that plate?).Actually, I cut the caliper mounting bracket (on the left fork) down some, and then drilled new holes in it. I did utilize the original top mounting hole on the caliper itself, and then drilled & tapped a new hole for the bottom mount on the caliper. Just as you did, I also needed to space the caliper over some to line up with the disc properly, except I was in no hurry (had no ride date set), so I made some nice looking aluminum spacers on the drill press.

Dammit!

07-31-2006, 09:51 AM

You changed the front fender angle a bit didn't you. :D

Red Rider

08-01-2006, 12:58 AM

You changed the front fender angle a bit didn't you. :DDammit Dammit!, you've got a good eye there. I changed the angle a bit, and moved the whole fender forward about 3/4". I needed the extra space & angle to allow clearance for the fork protectors to pass behind the portion of the fender that wraps around the fork legs. If I didn't do both adjustments, if & when I bottomed out the front end, I would have wasted the front fender & both fork protectors.

dizasterzrfun69

11-11-2006, 01:56 AM

hey red rider i know this is an old thread but im thinking about doing this crazy conversion. What should i plan on spending on some 85sx forks? I found some but $250 seems like it might be a little high.

Kevin

Derrick Adams

11-11-2006, 09:11 AM

Kevin, if $250 is out of your ball park, pass that deal along to me. They usually bring that and more. Kind of hard to come by.

Billy Golightly

11-11-2006, 10:01 AM

I just missed a BIN on ebay while I was out of town for my third set at $200 :mad: Anything under $300 is a steal as far as I'm concerned on these forks.

oldskool83

11-11-2006, 11:36 PM

man, looks like you went thru alot of work to do that tripple tree mod.

personaly i would of just designed a new set of tripples out ot alum. 6061-T65 or equiv. metal and had a machinest cut new one and press your stearing steems into the new lower tripple. i always worry about having things cut off and rewelded back onto somthing thats going to see alot of stress.

cool conversion. i saw a guy used KX250 forks on his bike once but i think he just bored the holes out on his tripple trees.

dizasterzrfun69

11-12-2006, 12:13 AM

Kevin, if $250 is out of your ball park, pass that deal along to me. They usually bring that and more. Kind of hard to come by.

it's not out of my ballpark, i just wasnt sure if they actually did cost that much on average. Maybe i can find them again one bay and buy them. Is anyone making triples out of chunks of aluminum for them yet? Anybody want to make me the triples/ weld up a set of triples if i get all the parts? I dont have access to a welder that would weld aluminum that good and i dont really want to trust some weld shop that doesnt understand what they are for.

Derrick Adams

11-12-2006, 10:37 PM

Wasn't trying to offend you or anything but yeah, thats a decent deal!

MTS

11-12-2006, 10:56 PM

Wasn't trying to offend you or anything but yeah, thats a decent deal!
It certianly is considring they retail for about 700$ a leg.:crazy:

dizasterzrfun69

11-12-2006, 11:00 PM

Wasn't trying to offend you or anything but yeah, thats a decent deal!

lol no biggy, i didnt take it that way at all. i've just never priced forks for anything actually and i really had the slightest clue as to what some little forks would go for.

Red Rider

02-05-2013, 12:20 AM

Well after the first ride, on the new forks, back in mid-late 2006, it was obvious that I should have done more homework on the effects of rake/trail, trailing axle/leading axle setups before I undertook this project. The combination of switching to leading axle forks & keeping the factory rake, built into the triple clamps, led to less than desirable steering/handling traits. Basically, the steering is very twitchy because of the lack of trail with the current setup. Over the past 6 years, I've gotten used to, and adapted to, the handling characteristics, but I longed for the factory handling finesse once again, and was looking into different options to machine a new, clean-sheet design.

Then, back in Dec. 2008, my brother (Mr. Sandman) decided to switch over to a set of these same forks, and as it turns out, a friend of his, who just so happens to have a manually operated mill, was willing to machine him a set of triple clamps. My brother asked if I could design a new set of triple clamps, without my handling woes of course, for his bike. I then asked, if I did, could I get a set machined as well. The answer was yes, so I started doing my homework on rake/trail, reading everything I could find on the subject, so I could design the new triple clamps. After seeing builds with inverted forks from Jason Hall, Derrick Adams, & Black Sheep, I decided to contact them as well for any input on the subject, so I could hopefully avoid any pitfalls in my design.

I had the blueprints finallized in early 2009, and we purchased the 1.5" thick, 6061 aluminum in March 2009, and dropped it off at the friend's house, who would be working on them at his leisure. Since his friend wasn't charging us for the machining work, we had a hard time bugging him for progress updates. As a result, the progress was slow. Finally, in early 2010, we get a pic of the progress to date, and then a few more as 2010 rolls on. These are pics of the top triple clamp(s).

Red Rider

02-05-2013, 12:40 AM

Then we start to see some progress on the bottom triple clamps.

Red Rider

02-05-2013, 02:49 AM

There wasn't any progress on these at all in 2011. Then around Mar. 2012, my brother gets a call from his friend because he needs to get together with us, as he has a few questions before he can finish them up. We finally manage to coordinate all 3 of our schedules and meet up in Aug. 2012. We spend about 6 hours in his garage that day, while he finishes the milling on all of the sensitive dimensional areas of the clamps. At long last, all of the machining was finally done, and the ball was in my court to finish them up.

Pic#1 shows the top sides of the top & bottom triple clamps.
Pic#2 shows the bottom sides of the top & bottom triple clamps.
Pics#3-4 show the forks installed in the new clamps. Those forks are a tight fit without any pinch slits yet, and those clamps have sharp edges, fresh from the machining process. Lots cuts on the hands for those last 2 pics!

Red Rider

02-05-2013, 02:32 PM

To prevent any more blood loss from handling these, the first order of business was to file down all of the sharp edges. Then in Sept. 2012, I got all of the pinch bolt holes drilled, countersunk, & tapped for the stainless steel allen bolts. Next, the pinch slits were cut. The holes for the handlebar clamps were also drilled in the top clamps. Here's the progress up to that point.

RubberSalt

02-06-2013, 03:55 AM

Pretty.

This gives me al kinds of ideas

Red Rider

02-08-2013, 04:11 AM

Thanks RubberSalt. We're just about caught up to the present now. The first 2 pics were taken in mid-January 2013 right after polishing, and the last 2, about a week after that. More to come as I get them & the forks mounted up.

fire1

02-08-2013, 06:24 AM

Awesome job as always !

aldochina

02-09-2013, 01:19 AM

those are rediculous! They look awsome, hope they make it handle how you dreamed!! Too bad you couldnt have 20 of those made!! but then they wouldnt be as cool to have on your bike!!

Red Rider

02-10-2013, 03:28 AM

Thanks fire1 & aldo.

More spy photos: Triple clamps are installed with new 30wt. ball bearings & quaker state racing grease. The forks are temporarily installed while I reproduce some custom parts for Mr. Sandman's bike. I still need to rebuild the forks, but that will have to wait for the next set of days off.

Red Rider

03-17-2013, 10:02 PM

Many sets of days off have come & gone, and I haven't felt like rebuilding these forks because it's such a nasty, messy job. In the meantime, I've been working on other less dirty (which equals more fun in my book) items, like the graphics for the fork guards, modifying the fork's top caps to accept some new, trick, fork bleeders, and the 350X headlight shroud v2.0. Since most of the fun stuff is almost complete, I finally decided to tackle the forks last night. Both fork legs have now been rebuilt with new bushings, seals, o-rings, dust wipers, and 10 wt. oil.

She's all back together now, and sitting on 3 wheels again. I just need to finish up the headlight shroud now, then re-install.

Dirtcrasher

03-26-2013, 11:19 PM

WOW! You had a great conventional machinist (no CNC); his work looks fantastic and I can't imagine how many hours it took him!

LOOKING GREAT!

Red Rider

03-27-2013, 02:21 AM

WOW! You had a great conventional machinist (no CNC); his work looks fantastic and I can't imagine how many hours it took him!I don't know how many hours he has invested in these, & the other set he made at the same time, but he chipped away at them, in his spare time, for over 3 years. Thanks for the compliments. I'll be sure to pass them on to the master machinist.

chuk85

03-27-2013, 02:38 AM

Red Rider

03-29-2013, 04:02 PM

ive wondered if you could just chop up the stock triples (like you did) but i didnt know if they would be as strong or not, either way they look AMAZING and who ever the machinist has got some skill for sure. think he may wanna do another set??????:naughty:

i just read page 4.

do you think the rake/trail could be figured out? (like on the stock/choped set) how do you check rake and trail?Chuk, thanks for the compliments. Even though I didn't like the way my bike handled with the cut & welded, stock, triple clamps, I rode it that way for several years, and the triple clamps showed no signs of cracking or fatigue anywhere. When I was designing the new clamps, along with input from the board members that I mentioned earlier, I referenced these 2 websites: http://www.performanceoiltechnology.com/rake_and_trail.htm
http://www.wellsphere.com/biking-article/trail-fork-rake-and-a-little-bit-of-history/236726

chuk85

04-05-2013, 02:01 AM

ohhhhh now i get it, seems kinda like caster in a car on how the steering speed/handling is effected. thanx a bunch! this will help alot when i try and get a set made

Red Rider

04-05-2013, 03:35 AM

Jason Hall, on the boards here, makes an entire kit to do add inverted forks to your R. Try contacting him when you're ready.

chuk85

04-05-2013, 11:29 AM

last i checked they said there sold out in the store, does he make them to order?

Red Rider

04-05-2013, 01:21 PM

I don't know. You can try sending him a PM. I know he's usually pretty busy, so it might take a while to get a response, but it's your best bet.

JasonB

04-05-2013, 04:39 PM

Theres actually another guy on here planning to start making these (Cant say who since its a secret ;P ) but they should be coming out sooner or later.

chuk85

04-06-2013, 12:06 AM

oh really?????????? well if you run into this guy tell him i would love a set. i want to use cr forks choped down and maybe do a 10inch front wheel to

Red Rider

09-26-2013, 03:57 AM

Wow, I knew it had been a long time since I seriously messed with this headlight shroud, but over 6 months? Geez! Been a bit hot here in Vegas over the summer months, toss in some more important priorities, add in some general laziness, and that adds up to 6 months. Anyway, I've been chipping away at the shroud the last couple of weekends, and along the way I taught myself how to do some aviation-inspired, flush-mount riveting to get this thing finished up. Now I just need to get some red paint on it, and mount it up.