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Brtp4 03-07-2011 09:33 PM

XR250R Build
Back in January of 2010, we had a break in the weather and I went on a ride with some local friends. I was riding my XR650L, which is now fairly modded. It's old, but competent. On this ride, it was warm, and a mix of mud, melting snow, and maybe a little ice. Trails were not that technical, but greasy. Looked like this:

After getting worked with the weight of my heavy XR650L, it was painfully clear I needed a lighter bike for singletrack riding. I do not really have the youthful sharp reactions to ride a 2T well any more, so I was thinking about a small to mid sized 4T bike, that could be plated. Being a project kind of guy, I also wanted something that I could build from the ground-up. Once done, I would ride it for a while and eventually keep as a spare.

My shortlist had several models, ad I was hoping for something hammered or blown up so I could get it cheap. A person I knew mentioned "I know of a blown up XR250R, a newer one.". It was not the first bike on my list, but I called the seller, The bike was in good condition, but did not run. He wanted to cut a deal over the phone, explained that it seemed like it broke the cam or something. He wanted $850, I told him that if I had to commit sight unseen, I would go to $650. He agreed. Hopped in the truck and drove down from Bend to get it.

It was a bit neglected but had very little use:



motowest 03-07-2011 09:42 PM

It's nice when things work in your favor. Much better than hearing an unexpected list of parts that are needed ($$$$).:D

Garthe 03-07-2011 09:48 PM



Brtp4 03-07-2011 10:06 PM

I power washed it on the way home, cleaned up really well:

First thing I did was drop it off at my friend Matt Worbes shop, M-Tech Motorcycles to diagnose. After a day he calls me. BTW, Matt is a man of very few words.

"Your bike is ready."

"What do you mean "ready"?"

"I mean it's running."


"Yea, running. Pilot jet fell out. Put it back in and it fired right up."

$650 for a running 2003 on the original tires. I was pretty happy.


Brtp4 03-07-2011 10:31 PM

Basic Maintenance
Back when I was talking to the PO, I asked him to check one thing on the bike for me. The swingarm pivot bolt. On XR250s and 400s, because the pivot blot passes through the motor, it cooks out the grease, the bushings freeze on the bolt, and make it difficult or impossible to remove. It is the achilles heel of these bikes.

I really did not think I would have an issue, since it was fairly new. I was kinda wrong:

I squirted things up, waited a day, and started by tapping on the nut with a plastic hammer, then a ball peen, then a mini sledge. Holy smokes, it would not budge. I then took an old extension and started wailing on it. STILL nothing. So I tipped it 45 degrees, lubed the heck outta it, and went at it the next day. This time I had my wife turn the other side with a ratchet while I pounded. It finally came out:

Pretty surprising how dry and rusty it is, for a bike in that condition. Even left a pile of dust on the floor:

After a lot of wire wheeling. Bolt was fairly pitted:

(sorry, cell phone pic)

Just to be sure, I replaced the bolt and bushing because of the pitting. I probably could have reused them, but bought a new OE bolt ($65....f me.....) from Honda along with new bushings. I saved the old one, just in case. Bearings were fine, only the bushing-to-bolt interface was fouled. Greased everything back up and put the bolt in.

Afterward, the extension became too mushroomed to fit into a socket.



Brtp4 03-07-2011 11:33 PM

The first thing was to fix the awful playbike riding position. Honda mounts the bars quite rearward, and gives them a lot of sweep, putting the rider back and making it really hard t weight the front wheel.

Added some CR Mid bars, good height with little sweep. I also got a new Billet Racing Products upper triple, that places the bars much more forward:

The clamps move things about 1.25" forward, and the bars place your hands another 4.5" fwd:

When I pulled the triple off, things were dirty:

That is not rust on the star nut, it is this Norcal clay. I pulled everything apart, greased all the bearings, and put the controls back on:

I skipped the handguards at the time, will add them later.

Brtp4 03-08-2011 12:39 AM

Bike Choice
While I was researching the little XR, a friend told me about an article in an old DIRT BIKE magazine. The January 1999 issue had a comparison test of 4 XRs done at Scott Summers ranch. Summers and 6 other riders compared a stock XR250R, stock XR400R, a modified XR280R, and a modded XR440R at his ranch, a 4.5 mile loop, riders with mixed experience. Reprint of their lap times:

Name..............XR250R.........XR280R.......XR40 0R........XR440R
Parlin.............10:18.00.......10:08.16......10 :06.27.......9:59.67

This does not suggest that the XR250R is as fast as a modern bike, but if set up right, it would work for me. I figure the 250 kept up for a few reasons, first, because it is smaller, lower, and has a wheelbase 3" shorter than a CRF250/450, a big difference. Also, because it has less power, it was easier to ride, which would be good for me.

hanksmybuddy 03-08-2011 08:04 AM

Excuse me sir but do you think I could get a written report mailed to me on this in the form of a book report. I'm very interested in the epifany thing you talked about in one of your earlier posts. To be honest with you that thing looks like a rat trap. I'd part it out before you have another epifany or something. :wings

Dakar Dan 03-08-2011 01:04 PM


Originally Posted by Brtp4 (Post 15364441)

I skipped the handguards at the time, will add them later.



Hey, is that an old skool Stumpjumper there?

Brtp4 03-08-2011 01:26 PM


Originally Posted by Dakar Dan (Post 15368203)
Hey, is that an old skool Stumpjumper there?

One of the very last steel frames. Got it as a frame only. Built with XTR and a Judy, now I have it set up for wifey.


HighwayChile 03-10-2011 10:50 PM

come on keep postin' :1drink
I agree with the less being more, I"m a slacker when it comes to riding and although big HP is fun in the right area its a hand full in others. I started on a '65 honda trail 55 ( thats an early Advbike, probably where BMW got the GS idea ) 43 years ago, I'll probably end up on a 50 ( hot rod Derbi, maybe) if I make it long enough.
the rougher it is the more fun you will have, the fast sections well that when to bring big red.

thought of a new front end, USD? rear shock swap?

Brtp4 03-11-2011 10:20 PM

Siince I was in there for the swingarm bolt, I figured I would do some maintenance and re-springing on the rear suspension. I pulled the rear linkage and the shock off the bike:

It is always important to spring the rear for your weight. I got an 12.0 spring from Eibach:

....and found Les from LT Racing (, who has a couple XRs, one that is really trick and one that is absurdly so. He has links to them on his website, click here. Several people recommended him so I sent the shock to him to revalve for my weight.

Cleaned up a bit, and of course always, always, always pack things up with grease:

Swingarm back on:

And suspension linkage:

Brtp4 03-11-2011 10:58 PM

XR250s are playbikes, not race bikes. But the designhas good characteristics: short wheelbase, 6 speeds with fairly close spacing, a Honda, and a mild state of tune that responds well to mods. A CRF250 has considerably more power, but some folks have raced the little 250 with good success. Here is a horsepower graph of the two:



n16ht5 03-12-2011 01:30 AM

wow, looks like a great build! Going to be one nice bike.

I have an 01 XR250R, wouldn't trade it for anything. Definitely subscribing to your thread. I never knew about those triples, going to look into that. How do you like the FMF ..Q4?

My bike doesn't have much for engine mods... mostly everything else. when it needs a teardown I'll open it up to 300CC

Brtp4 03-12-2011 06:55 AM


Originally Posted by n16ht5 (Post 15397968)

That bike is nice, the ride looks even better.

The Q4 is really nice. I have a PC pipe on my other bike, the FMF is quieter.


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