XR250R Fork oil

[creeky]

Has anyone tried 2.5 fork oil on their 250R?

[Chuck.]

What year?

 

 

[creeky]

2002 stock forks.

[Trailryder42]

The stock oil is Honda SS-7 which is a 5w. 

I would think you might notice your valve damping for a given setting react a little faster but that's about it.

I think 2.5w was what I ran in my 400 after I did the shim stack mod.

[creeky]

Thanks. I am happy to report that I got back into riding last year after recovering from some health issues that I thought had brought on the end of my dirt riding. Anyway, the '02 250 that I have currently is what I am working on. It already has the 77mm piston and a full Baja Designs lighting kit. It had been sitting for a few years so I had to do the usual drill to remedy all the stuff that comes with disuse. I am considering doing the shim stack mod and trying the 2.5 wt oil to see if it will improve the damping through the last 50-60% of the travel. Do you have any thoughts on this?

[Trailryder42]

5 hours ago, creeky said:

Thanks. I am happy to report that I got back into riding last year after recovering from some health issues that I thought had brought on the end of my dirt riding. Anyway, the '02 250 that I have currently is what I am working on. It already has the 77mm piston and a full Baja Designs lighting kit. It had been sitting for a few years so I had to do the usual drill to remedy all the stuff that comes with disuse. I am considering doing the shim stack mod and trying the 2.5 wt oil to see if it will improve the damping through the last 50-60% of the travel. Do you have any thoughts on this?

When I saw you posting again recently, it dawned on me that we hadn't seen you around here in a long while. Glad to hear you're back at it.

I was going to say that the shim stack mod mostly effects the beginning of the stroke, but even if the suspension is further into the stroke when it takes a hi speed hit, the shim stack mod will allow it to react faster to it. With the fork spring compressed so much more at 50%, getting in to the meat of the spring, the quicker flow thru the damping of the shim stack would have to make that hit less harsh.

Edited January 29, 2021 by Trailryder42

[creeky]

I decided to go ahead with the 2.5 fork oil, set the oil level according to the book. Also decided not to do the shim stack at the same time, just one mod at a time to determine how much (or how little) of an effect resulted. If it ever warms up and dries up around here, I'll be able to ride a bit and see if anything changed. 

[bajatrailrider]

We use 3 wt rear shock oil in xr fork . Since the 250 fork has no rebound adjuster. We have used 2.5 wt for years but rebound too fast. It depends what brand fork oil all different. We have used last ten years 3 wt rear shock oil in forks 

[creeky]

8 hours ago, bajatrailrider said:

We use 3 wt rear shock oil in xr fork . Since the 250 fork has no rebound adjuster. We have used 2.5 wt for years but rebound too fast. It depends what brand fork oil all different. We have used last ten years 3 wt rear shock oil in forks 

Thanks for the input. Are you using stock springs or aftermarket?

[bajatrailrider]

4 hours ago, creeky said:

Thanks for the input. Are you using stock springs or aftermarket?

.43  gold valves many mods  others stock forks all 3wt oil. We are really not happy with the 250 forks. The real fix xr400 forks 

[creeky]

48 minutes ago, bajatrailrider said:

.43  gold valves many mods  others stock forks all 3wt oil. We are really not happy with the 250 forks. The real fix xr400 forks 

Thanks. I do have a pair of XR400 forks, but no triples or axle, I'll see if I can come up with them if I'm not satisfied with the stockers. 

[bajatrailrider]

We are using xr4 forks on wr450/xr250/crf230s . 

[creeky]

10 minutes ago, bajatrailrider said:

We are using xr4 forks on wr450/xr250/crf230s . 

Since that works where you ride, probably works everywhere. 

[bajatrailrider]

For trail riding they work well I think back east . The wimpy 250 fork more useable.On high speed trail baja the 250 41mm fork . Too much flex no rebound adj. Xr4 fork fixes all those problems 

[creeky]

The weather has finally improved to the point where I can ride, pretty well dried out, temps in the 50s, time to find out if the 2.5 fork oil is an improvement or otherwise. I spent a little over 2 hours on the bike yesterday, about half and half pavement and dirt. I had to play with the shock spring preload, clickers on both ends for a while, finally achieved a decent balance. The forks are better. Compression damping is smoother and doesn't firm up too much at the bottom of the stroke. Rebound hasn't changed much, maybe a little quicker than before. The forks soak up bumps and ripples and deep ruts just fine. I regeared with a 14/45 combo to reduce engine rpm at pavement speeds. Works great. I can cruise at 60-65 without any complaints from the engine. I actually like the gearing better than the stock 13/48 for dirt, less shifting, still plenty of power for climbing, 1st gear is no longer a  stump puller. I'm going to leave it as is for the time being.

[TapXR400]

I am getting ready to replace my fork seals again, this time with OEM honda seals, XR400. Any of you guys tried 0w20 synthetic motor oil in your forks? I was thinking about giving it a shot.