86 250R fork upgrade?

[vroomy]

hi does anyone improve 250R forks or can it be done? i find they bottom out too quick on the whoops and jumping, i see alot getting around with custom fitted inverted forks is this the only route to a better front end? i would prefer to keep original looking. Also does Axis or another shock company do rear shocks for these?

[mohadib]

http://www.3wheelerworld.com/showthread.php/141223-250r-shock-from-EBay

[max]

Look up progressive fork springs. They make a stiffer spring which helps out alot for the liquid Rs

[dirtjunkie85]

I also took mine to a guy that was local. I'm not exactly sure what all he did but instead of just putting stiffer oil in the forks he did change a ton of different components. I would just check out around your local places and see if they have anything like that.

[4x4van]

If everything is in good working order, they shouldn't be bottoming out very easily unless you weigh 250+ pounds. The valving can be re-worked (generally not cheap, but effective). Springs can be replaced. First thing to try, IMO, is to fine tune them with air pressure; Try 2-3 lbs of air pressure. It's such a small volume that you really need a hand pump designed for front forks, but you can stiffen them up significantly with air. Fork air pumps are not too expensive, and they are really the only way to add/adjust fork pressure.

[audioworks04]

Can also run pvc spacers to help stiffen your springs along with a thicker oil to slow the valving down are night and day differences.

[Kintore]

x2 with Max, progressive springs and a inch or two PVC pipe in there work MINT. That or sockets, used them too.

I ran prog springs, sockets and some heavier oil. The air valves at the top are for releasing pressure, not putting it in.

[4x4van]

The air valves at the top are for releasing pressure, not putting it in.
Actually, although the stock setting is 0psi, they ARE designed for putting air in, and the owner's manual recommends adding air for just the situation that the OP states. From the Manual:

http://i679.photobucket.com/albums/vv159/4x4van/ScreenShot026.jpg

In fact, believe it or not, springs are not actually needed in front forks if you are running air pressure. In the late 70's/early 80's, when I was racing motorcylces in the desert, my front forks used air alone (around 8-12psi if I remember correctly); no springs at all. A bit of air also helps fork seals last longer. When "air" forks first came on the scene, we drilled/tapped the fork caps of bikes that didn't have them, added an air valve, and removed the springs completely. My brother also owned a '75 YZ250 that had an aftermarket rear shock with no spring; used pressurized nitrogen instead.

[vroomy]

so do the forks work like Fox Evol shocks off a quad? im actually running those on one of my quads and have the pumps for them which im assuming would do the job?

[Kintore]

hmm I stand corrected, thanks for the info

[4x4van]

so do the forks work like Fox Evol shocks off a quad? im actually running those on one of my quads and have the pumps for them which im assuming would do the job?
Yeah, they are like that, although most of today's air forks also use springs, relying on air to adjust that spring rate only. Your Evol pump should work. Typically, forks use low pressure (5-8 lbs), and because it's such a small volume, a tiny amount of air makes a big change in pressure. That's why a fork pump is normally used; they usually look like a large syringe with a gauge and bleeder valve on them.

Here's the problem with getting an accurate pressure. Because it's such a small volume, just removing the pump can cause a loss of 5 lbs or more. So you need to do some experimenting. Pump the forks up to about 15lbs, then remove the pump. Check with a hand held gauge and you will find that you have likely lost some, perhaps 5 lbs, just from removing the pump. Check again, and you will likely have lost another 4-5 lbs! Once you do this a few times, you can get a feel for how much pressure is lost when you remove the pump, as well as when you check with a gauge.

Once you have that info/feel, then you can add air pretty accurately. For example, if your testing has shown that removing the pump loses 5 lbs, and you want 8 lbs...then use the pump to pressurize your forks to 13 lbs. When you remove the pump, the "pssst" will drop you to your desired 8 lbs.

Clear as mud, right! :)

[Dirtcrasher]

IDK the part number.

That's how I got PS. DEEPA gave me the number.............It was 59$ for a set. They can't hurt for sure.

[vroomy]

is there a racetech cartridge emulator that will work in the 250R forks? i read up a bit on them and they sound pretty amazing

[Billy Golightly]

is there a racetech cartridge emulator that will work in the 250R forks? i read up a bit on them and they sound pretty amazing


Yes...and they work pretty well. I did quit a bit of research with mine and got the right model to work in the Rs. I've been running them about 3 years now. I plan to list them in the store soon.

[ceaserthethird]

Yes...and they work pretty well. I did quit a bit of research with mine and got the right model to work in the Rs. I've been running them about 3 years now. I plan to list them in the store soon.

RaceTech cartridge emulator ~ Sounds interesting, Let us know how they work Billy.

[JasonB]

put them in the store so i can buy them :D suspension refresh is next on my list

[barrett8]

i might also be interested in them

[rray62]

RaceTech is currently doing a full suspension build for me, but evidently the biggest flaw in the forks are the tubes themselves. Mine were worn beyond repair and I thought they were still functioning properly. I'm having a heck of a time trying to find some tubes in good shape or someone who custom builds them.

[Dirtcrasher]

I got a NOS set off 200X,350X and 250R some as cheap as 250$. I couldn't touch a set a few years ago for 600$ or better.

Watched Evilbay, seems like people are selling everything to get some cash........

[Billy Golightly]

RaceTech cartridge emulator ~ Sounds interesting, Let us know how they work Billy.


They work very well. They take some time to get dialed in, but its a night and day difference. I won't say its like bolting on a pair of inverts (because its not) but boy it does make a difference.

[vroomy]

Yes...and they work pretty well. I did quit a bit of research with mine and got the right model to work in the Rs. I've been running them about 3 years now. I plan to list them in the store soon.

any chance you could organise me a set?

[vroomy]

anyone have the part number for the correct RaceTech emulator?

[torque]

x2 with Max, progressive springs and a inch or two PVC pipe in there work MINT. That or sockets, used them too.

I ran prog springs, sockets and some heavier oil. The air valves at the top are for releasing pressure, not putting it in.


when going to a heavier oil would you use a suspension fork oil? and what weight fork oil is just heavier than atf?