XR250L and exchangeable parts from other XRs

[CHIEFCULPRIT]

As I now have the mod bug and want to see what I can do to improve my bike, I now have more questions than ever and my searches seem fruitless. Parts seem very limited at best and I love my bike too much to sell and go for another bike. Plated bikes (in CA = gold ticket for now) seem hard to find or expensive and the newer the bike the more motor maintenance they seem to require. Something about the XR being just down right reliable.

On my wish list:

XRs Only skid plate

250r header and new pipe (may just go all new XRs Only)

280 kit when motor needs the rebuild (who has the most reliable kit)

Suspension work

Questions running through my brain:

Can I put an XR4 or CRF450x front end including wheel on my bike? or Should I rebuild the OEM forks 1st to be stiffer?

On the XR250L I have whats called cushion drive. Can I goto a fixed sprocket hub? Would a newer XR400 rear hub work? Am I looking at problems with a fixed sprocket and the tranny?

[cwcarter]

Your best to find yourself a wrecked 250r and pull all the goodieis from it. I think they have different cams, hotter ignition, better carb, larger headers , fixed hub and better suspension.

If you want to go the usd way, the easiest way would be to find a front end from a 89 90 cr 250/125. they'll bolt straight up and still be a major improvement over the xrl's boingers.

[ramz]

For some tips on what interchanges, see: XR250L Project

Also, read XR-250L jet part numbers thread 7349811 and the thread it refers to and the references there also.

The valve adjustment thread 715732 has the carb AP mod in it ?

[RedRider3141]

As I now have the mod bug and want to see what I can do to improve my bike, I now have more questions than ever and my searches seem fruitless. Parts seem very limited at best and I love my bike too much to sell and go for another bike. Plated bikes (in CA = gold ticket for now) seem hard to find or expensive and the newer the bike the more motor maintenance they seem to require. Something about the XR being just down right reliable.

On my wish list:

XRs Only skid plate

250r header and new pipe (may just go all new XRs Only)

280 kit when motor needs the rebuild (who has the most reliable kit)

Suspension work

Questions running through my brain:

Can I put an XR4 or CRF450x front end including wheel on my bike? or Should I rebuild the OEM forks 1st to be stiffer?

On the XR250L I have whats called cushion drive. Can I goto a fixed sprocket hub? Would a newer XR400 rear hub work? Am I looking at problems with a fixed sprocket and the tranny?

Here are my answers based on OTHERS experiences:

I bought a spare rear wheel from a guy with an XR250L who had used an XR400R wheel instead. I don't know what spacers he used only that he used the OEM XRL axle. I don't see a huge advantage in doing this other than weight savings. If you spend alot of time on the road the cush drive is meant to protect the tranny against excess vibration and jarring.

I just saw an xr250L on CL with XR400R forks. I didn't know it could be done until now. I'm trying to get the owner to send me a picture. The forks are different diameters (41mm vs 43mm) so he must have used the 400 Triple clamps and made his own steering stops.

IMO after riding my L with Cartridge emulators and the 400 forks with semi-cartridges. I would go with whatever option you can do for the least money. Both ride very nice and are well worth it over the stock L forks.

[CHIEFCULPRIT]

Rams & RR,

Thanks for all the info and help. Now when I tore my bike down last, I use your 250 project as my guide (although this link reads differently and better info, are there different versions out there?), for the stuff I could afford to do. I didn't do any of the engine mods but most of the other stuff. Left the battery but went through the wiring harness and cleaned it up and removed the wires from the kick stand and kill switch completely. Weight savings were not my main point just remove the extra do nothing items. Air box, exhaust (even though the headers are L) I ground out the crap inside and removed the baffle from the pipe. The carb got the most extensive focus, removed whatever parts I could. Then I rebuilt the carb and jetted 40/122, blasted every hole with carb cleaner and soaked in the stuff for good measure (can't tell you, how glad I was to wear safety glass - looked like I was blasting through swiss cheese). I dont have needle settings so I used 2 #6 washers epoxied together to lift the needle about 2mm. After cleaning the inside put back together and went to work on the accel-pump. Measure the total movement of the pump shaft then removed the spring on the levers and wired the the 2 pieces together and bent the tab to be touching the pump shaft. When the float bowl is full I can shoot a stream roughly 10ft or more out of the carb.

[RedRider3141]

I got in contact with the seller of the XR250L with XR400R forks. Even though someone already purchased the bike he was willing to send me a picture and some more info. Here is his reply:

Weused the XR 400 triple clamps and machined special bushings to adapt them to the XL250 stem & bearings.

I don't quite remember the axle & caliper pieces but it wasn't too hard.

My friend put on the forks; and I have an email into him asking about the installation.

If I hear more from him I'll post the info.

Here is the bike, click on the picture and then Google will let you zoom in.

[Tremelune]

L's have a cush drive? No shit. You'll probably want to keep it on there unless you really don't do much street riding (stop and go).

With regard to CR forks, this thread mentions a distaste for the early CR forks that bolt right up.

[CHIEFCULPRIT]

Ok I was looking around and stumbled across a 91 250R for $500. I called on it and got it down to 400. I was just really looking on parting it for my 94 250L. The seller wanted to get rid of it because he just didnt need it and needed the cash. Went to check it out and noticed its got AL BAKER stuff (skid plate and longer cooling fins welded on and I think a pipe) so I would guess there is a bore job done. It started with no choke after about 10 kicks, and rode it. I heard some clacking in the valve area but it had plenty of power. It started from a dead stop in 2nd no problem and was able to lift the front wheel in 2nd and 3rd, about a 5 minute ride revin it out and shifting through the gears. Leaks oil from the head gasket but oil doesnt smell burnt, no back firing or missing. Even if it needs alot of work motor wise I think it was a pretty good deal. The forks felt to be in good shape and the rear shock was the same. Larger header and supertrap style pipe. Not a bad deal for a parter, plus I can use the L parts to possibly rebuild it as a buddy bike. A project I dont mind.

[piku303]

my plan is to replace the L headers/pipe with the stock R units, grind inside headers...and remove some airbox crap. heres where i need your advice...

keep the stock carb and do the accelerator pump mod...or replace with an R carb?

if its really worth it to replace the L carb with the R i want to do that at the same time as doing the intake/exhuast mods so i dont have to rejet the L carb and then jet the R carb later when i get it.

whats the performance difference between the R carb and a properly jetted L carb with the accel pump mod? from what ive heard the R carb is easier to find jets for but ive also read that its not that much harder to properly jet the L carb. ideally id like to save money and stick with the L carb but if the R carb does offer noticeable performance increase it would be worth it.

thanks guys

sam

[CHIEFCULPRIT]

Sam,

Don't spend the money until you try the L mods 1st or unless you really want the R carb. Jetting is cheap and rebuild the carb is easy. I did read in an old thread that the main jet holder on the L carb is the same as the R , just smaller aerator holes on the L holder. If that is the case (which I am lookin into and will do if it works) go up from 122 stock to a 128 or 130 with the R main jet holder. I would work with the same model years 1st. After redoing my carb, really opening up my air box I noticed a big difference, and that was even with the L header. The bike starts easier and doesnt hesitate or cough on climbs anymore and just feels stronger. PM me if you need help, I'm no pro and know just enough to really be dangerous, but thats where the fun is...

[piku303]

chiefculprit...im getting the bike tomorrow so ill be pm-ing you once im no longer satisfied with the stock power...and danger is my best friends middle name.