02' CR 250 New Look & Advice

[1998RM250]

CR 250 New Look & Advice

Hey guy's I decided to let my buddy ride my CR250 for the first time yesterday, he has a CRF250. Hit the throttle once in 2nd and over the bars he went, but was nice enough to buy me a new Throttle Jockey seat cover I've been wanting for dumping the bike! The bike is one ofthe cleanest dirt bikes I've ever seen, and has been taken care of so I want to have the bottom end rebuilt. I was thinking of buying a Wiseco or Hot Rods bottom end kit, then stripping the motor down and bringing it somewhere to have the cases split (top end is fresh). If I buy all the parts (figuring around $200) what should I expect for labor just to split the case and put a new crank in (I would remove the motor/top end, flywheel etc)? Also the RC Valve cables are getting worn and adjusted all the way out, where is a good place to find them, preferably motion pro? Here's a few pics of the bike, let me know what you guys think of the seat. :cool:

After new fender decal:

BEFORE:

 

[Dirtjunkie85]

That's a sweet ride!

 

[2-Strokes 4-ever]

Nice looking bike.

"hit the throttle and went over the bars"...?

 

[1998RM250]

Thanks guys, yeah he hit the throttle in second gear on the pipe and flipped it backwards I meant. Funny part is thats I was going to video tape him riding it to see how it sounded, but I decided not to! Also the previous owner has an 80's CR500 parts bike laying around and I wanted to do the AF conversion, other then tig welding some mounts what all would be needed to swap the 500 motor in this already beast?

 

[2strokerfun]

Also the previous owner has an 80's CR500 parts bike laying around and I wanted to do the AF conversion, other then tig welding some mounts what all would be needed to swap the 500 motor in this already beast?

Quite a bit of engineering and modification. But it obviously can be, and is, done. Radiators clearance, building a pipe, gas tank clearance and other issues all have to be addressed. I'm sure this particular conversion is covered somewhere pretty extensively on the internet.

 

[Shagy100]

to convert the bike to an AF is quite hard. I have been building one since last january but mine is a kx250f chassis with a 250 ts motor. The main thing is sectioning the frame so the pipe goes through it. One person to talk to is AJ at service honda. hes a really nice guy and can give you some good insight

 

[IndyMX]

Thanks guys, yeah he hit the throttle in second gear on the pipe and flipped it backwards I meant. Funny part is thats I was going to video tape him riding it to see how it sounded, but I decided not to! Also the previous owner has an 80's CR500 parts bike laying around and I wanted to do the AF conversion, other then tig welding some mounts what all would be needed to swap the 500 motor in this already beast?

I'm thinking that if you aren't comfortable with splitting cases on that motor, you probably shouldn't tackle the fab work it would take to swap the motor.

And again, for what it's worth, AF500 is a trademark. To have one, you need to buy one from Service Honda. Just saying. ;)

 

[1998RM250]

The previous owner was using castor oil, should I stick to the same kind since it's a different type of premix oil?

 

[IndyMX]

I personally feel that whole sticking with the same premix oil the other guy used is a total myth..

Pretty much the same as feeding your new dog the same food the last guy fed it, never had a problem with either, in my experience.

As long as both are getting a quality product, and your giving it the right amount everything will be fine.

 

[whenfoxforks-ruled]

Get the crank straight from wiseco or hot rods. The cheapy outlet stores will send you a rebuilt crank, in the proper box. Same with the bearings! Unless your name is AJ, you can only imitate, the building of an AF. And many, home made ones, end up broke. Much, depends on the rider to be sure. Stick with the oem oil ratio, unless you need more power. Then bump it up to 24 or 20 to 1, rejet, hang on, and always wear boots when starting!

 

[1998RM250]

Rejetting will be a whole nother' issue as I am unfamiliar with the Mikuni TMX carb. So far it seems pretty right on and never loads up, plug looks great. So if I bump the oil ratio up 24:1 I would need to go richer on the main for provide more fuel to compensate correct? I am still a bit concerned with the flywheel having slight side to side play, just enough to hear if you yank on it just right. No abnormal wear or leaking on either crank seals though and they are original.

 

[arnego2]

Crank bearing movement on the flywheel side is not good. How does the plug look like. And do you get some erratic high(er) iddle?

 

[1998RM250]

plug is a light tan color, it only idles high when you first start it up.. once it's warm it actually idles for about 5 min until it dies

 

[arnego2]

light brown tan is nice although I prefer a darker tan. How is your airscrew setting? and have you tried to wiggle the flywheel?

 

[whenfoxforks-ruled]

Reread the jetting links here on this site, many times if needed. Crank movement, kind of like you describe, NOT GOOD. A small degree of in and out, could be an issue with the right side, worn or missing parts, that hold the drive gear in place. Up and down, any at all, time for a bottom end job. With this on the plate, jetting is futile.

 

[1998RM250]

Great, there are NO reasonable shops within the area (southwest FL). I would do all the work myself, but I'm afraid I am going to mess up the cases. My buddies 94' RM 250 is sitting in my garage with a completely rebuilt bottom/top end and now it has an air leak somewhere we have yet to find.

 

[whenfoxforks-ruled]

Do you have the proper tools for case separation? Do you have the oem shop manuals? Do you have any current copies of Eric Gorrs books? Air leak on an assembled engine, remove the left rotor cover, get some non-chlorinated brake cleaner, and spray here and there, to find when the rpm shoot up. Or get/make a low pressure leak down set up. Search here, there are plenty that have done this, the tools from Motion Pro are an investment, and priceless.

 

[1998RM250]

All I really have is a nice assortment of Sk - wayne & snap on tools, motion pro flywheel puller etc. It was rebuilt by my friend who used the clymers manual. I was wondering on the 02' CR 250 can the crank bearings be replaced without splitting the cases? I've yet to pull the flywheel but there is a small amount of side to side play. Not sure the motion pro flywheel puller works on the CR, it was from my 01' RM 250 and is quality!

 

[whenfoxforks-ruled]

The 1 I have, fits darn near, every dirt bike I have worked on! I have not seen the clymer version on our bikes, BUT, I treasure my oem shop manual!

 

[1998RM250]

I need pick up books on the CR 250, seems like paying someone $600 labor is out the question, especially seeing I have the tools. My "friends" on their 450's are calling me out!

 

[1998RM250]

Finally got to pull the carb off, and it was actually pretty clean. It has a 380 main on the Mikuni tmx, air screw 1.5 turns out. I heard the 02's were jetted a lil lean and should go with a 400 main, especially if I want to run a 26:1 ratio correct? Also seeing a 20 degree temp drop so how would that effect it? It has a new BR8ES plug, fmf fatty, vforce reeds etc. Man i need a dyno lol...

 

[XRpredator]

I personally feel that whole sticking with the same premix oil the other guy used is a total myth..

Pretty much the same as feeding your new dog the same food the last guy fed it, never had a problem with either, in my experience.

As long as both are getting a quality product, and your giving it the right amount everything will be fine.

I gotta disagree. You go changing food on a dog and they start farting like a baby elephant

 

[julien_d]

I gotta disagree. You go changing food on a dog and they start farting like a baby elephant

farting and crapping all over the house, yup. Mabe 1st time ever I have agreed with Xpred. First time for everything, i guess....

 

[_JOE_]

My bulldog's like that, if you change his food he'll gas you out of the house.......

 

[1998RM250]

Took it for a long ride this weekend on the trails, seems like when its in the lower rpm's (I'd say around 4000) and you roll onto the throttle it made a "clack/clunking" noise sometimes. I went ahead and ordered a Wiseco bottom end rebuild kit complete with bearings and seals. The plan is to pull the motor, and head/flywheel etc then try to find a reputable shop locally to split the cases. I'm hoping to pay around $300 or less labor since the cases will be ready to split, what is your guys input?