ATC 90 Build with 140cc engine

[86trizinger]

I know there are tons of build threads around.. Haven't seen any threads with the lifan style engines used.

A lot of people said go with the 70 frame but I decided to go with the 90 frame instead because I had almost everything to get this up and going.

Here is what I am working with:

-ATC90 Joker frame
-YX 140 cc engine.. The side covers were cracked when I traded for it so I ordered a set of piranha -covers because I could get those the cheapest.
22mm carb
Pit bike exhaust
-Aftermarket triple trees
-Older Dirt Bike forks
-Rear disk brake

Went in pretty easy. Pit pit exhaust fit perfectly with a little bend.
I still need to Finish a lot.


http://farm3.static.flickr.com/2724/4443020985_b25884ffac_m.jpg

[86trizinger]

Overall I like the way it sits. I plan on raising the back fender up about an inch or 2 .
I may go with some shorter forks so I don't have to push them through the triple trees.
Also the triple tree seems very wide, but they ride so much better then no suspension at all.

Still have to find a rear caliper and master cylinder.

I have more parts supposed to be here hopefully before the week end.
Braided clutch and throttle cable plus a 1/4 turn twist throttle.

I am not trying to build a show bike , this is going to be a nice bike to ride on the trails with my kids.


http://farm5.static.flickr.com/4030/4443794168_21e9f36de7_m.jpg

[Jeepermc]

Cool! show us more!

[Vealmonkey]

There has only been 1 other build with a stock 90 frame with a gpx engine. And that trike is on its' 2nd or 3rd owner now. The original builders board name is edog. Look for threads started by edog and you should find the build thread.

[atc350xer]

bigger :pics: too... I have a new appreciation for the lowly 90 :D

[86trizinger]

for brakes I plan on using the same parts a 200x would interchange with.. Cr85 master cylinder and front caliper. I will of course need to have pretty short hose made.

[JohnR.]

No need to have a hose made. You can buy #3 AN lines with ends already on and you can get 10mm banjo to #3 AN fittings from Earl's. I made my own for the extended swinger on my T3 with parts I bought from www.behrents.com. The manufacturer of the lines is BCE. They come in a ton of different lengths and it ends up being cheaper to make your own than to buy one already done.

John

[86trizinger]

Locally I can have one made for less then $30 . Probably isn't worth it to make my own for that price. I just need the caliper to come so I can build the mount for it. It will bolt using the 3 bolts that hold the axle in place.. No modifying of the frame will be needed.

[JohnR.]

That's about what I paid to make my own stainless one. No real work involved, just screw the two ends on and have at it. Nice build, I'd bet the extra room on the 90 makes it a bit more comfortable than a 70.

John

[86trizinger]

Cables came today.. they stuck them in the mailbox after 5pm so I just now found them.. Hopefully they will go on tomorrow.
There is no place for a grab bar or exhaust mount on the frame. So I have to figure that out still.. But I don't want to weld to the frame.
It should be all up and running by next weekend hopefully but still need brake parts before I can complete the assembly.

Almost forgot I need a kill switch.

[Vealmonkey]

You are wrong about the grab bar. A stock grab bar fits fine, that is what I had on there.

[86trizinger]

I totally was looking at it wrong.. was thinking of how the 200x grab bar mounted. I plan to weld a bracket off of the grab bar to hold the exhaust.

[86trizinger]

I got the new 1/4 twist throttle mounted, but not totally happy with it. Its gonna require some adjustment to be perfect. The braided brake and throttle cable do look good though.

I couldn't resist. I had to plug the harness in and throw some gas in it.. It started on the 1st kick.. It sounds pretty mean, a lot better then my 200x. I didn't get to ride it yet since I am still working with the rear brake conversion. Hopefully I should maybe have a video of it this weekend running around the yard even though the brake will not be done.

So far I only have about 5 hours total in the assembly including all new bearings and making a new front axle.

[Vealmonkey]

As far as welding a bracket to the grabbar for the exhaust, I wouldn't do that. You are better off figuring a mounting method that is unboltable. A padded clamp on the grabbar and a clamp towards the end of the exhaust should do you pretty well. Or you could always a longer bolt through one of your grabbar bolts and attach your clamp and a couple extra nuts and washers to that. Sometimes grabbars get bent and it reallly wouldn't be the best place to mount the exhaust to the grabbar.

[86trizinger]

Good point. I will not have any more time this week though until late Friday night.

[86trizinger]

All wired up. Rear hub and brake rotor are all mounted. I did get to take it for a ride around the yard though.. I pulls a wheelie in 1st, 2nd and 3rd gears. Wasn't expecting that much power. It would have been crazy on the ATC 70..


List to do still:
1. The carb is still a little off though.. The air mixture screw is almost impossible to adjust though. It faces down right into the cylinder.
2. Rear caliper and master cylinder yet - I have a kx85 complete brake set up on the way for it I won off eBay for $5.00
3. Still have to make a couple brackets. One for the coil and one for the muffler.
4. Also I need to figure out the pegs for it still. I want to go with pit bike pegs but no money left for them yet.
5. Need to figure out the front fender. It has to be pretty wide to fill out the forks.

Then of course repaint the tank and fender.
Sorry I left the camera at my parent's, so no more pics yet.

[Vealmonkey]

I have some pit bike pegs and probably some 90/110 pegs somewhere in the house, we just have to find them! LOL And I have some mounts to adopt the forks to a 90/110 front fender so that should be good to go. What ever happened to that 70 you were going to pick up? We got to get you going and you have to help me get the suspension 70s together for 70 fest. Not including the dune buggy! LOL

[86trizinger]

I got a different 70 the other night.. Pretty decent shape but plastic is shot. Wheel are powder coated red and new tires on it. Tank is dented though. Sending a PM

[86trizinger]

Almost forgot about this thread. Got the rear brake all done. I wound up using all kx85 parts other then the rotor. I modified a set of bend pegs from a 70 to temporarily work until I get some pit bike pegs mounts. I already have new aluminum pegs sitting here for it already.

Carb is all sorted out.. It was actually I had a 13 tooth front sprocket so 1st and second gear were useless. I put a 15 tooth front sprocket with a stock rear one. We will have to see how that works.

The last thing before a test drive to is to extend the shifter about a inch and a half. Its a little tight right now for me.

[86trizinger]

Ok got most of the things done enough to ride it around for a little while. I need to go with bigger jets in the carb for the top end power but it is very quick down low . And its not even fully tuned yet.
I really don't know how a 70 would work with this engine. It pull the front wheel up with ease. The rear disk brake stops on a dime. I was really impressed with that.

Its a little uncomfortable for me to ride and a workout just to control it. I guess I shouldn't be going full throttle on off camber hills. I plan on getting some more pics this weekend when I have some time hopefully free.

[Jeepermc]

There any updates to this? I'm loving this thread...Not enough 90 love around here....Too many 70's...lol

Was this a Lifan 140? Bolt in pretty much...I haven't been able to find out much info on putting these things into 90's and how difficult/easy a job it is.......