cost of engine rebuild XR250?

[rapidmc]

so my room mate has a 1994 XR 250. We are thinking about rebuilding the engine.

What parts are necessary to replace on a rebuild?

what is the general cost for us to do it on our own VS having the shop do it?

thanks in advance for any help you can provide!

[off_road_4_me]

define rebuild.

New cylinder valves and piston? or the whole 9 yards?

[deeman]

I just paid $550 to have the cylinder bored out, new piston, rings and cyl. gasket. Also cylinder head "reconditioning" whatever that is, but the pulled the valves and reground the valve seats and added new guides.

Honestly, I think the cylinder head stuff was a bit expensive. If you only want to bore the cylinder out and get a new, larger piston and rings plan on spending about $250.

[MXP553]

You might get by with rings only and a cylinder hone. The bike has alot of years on it so I would pop for the piston kit. But you might be able to do it "El Cheapo". I would look at buying after market valves, getting lapping compound to hand seat the new valves and seals. Then a gasket set and a new ring. A timing chain is cheap as well and I would asume the stocker is stretched.

If the bottom end is shot, scrap it! Look on Ebay for a replacement. Cheap topend and rings = $200

Complete piston kit, and cheapo head fix. $350

[lanz]

First what is wrong with it now? Does it run? smoke knock? rattle? Assuming bottom end is good, is cam worn? I bought several good cams on ebay for $15-20. Import cam and lifters will run you $100, honda 3X that. If you have to bore it go with 77mm big bore, cost about same as stock. Top end gaskets $35

and get a manual. You can put bearings in backwards in cam and burn it up real quick. If bottom end is shot I need a stator for a 94.

[rapidmc]

First what is wrong with it now? Does it run? smoke knock? rattle? Assuming bottom end is good, is cam worn?

thanks for all your reply's guys!

As far as I know the bike smokes and burns a ton of oil. I dont think it has full compression. It still runs and rides.

If bottom end is shot I need a stator for a 94.

if thats the case its yours!

[off_road_4_me]

thanks for all your reply's guys!

As far as I know the bike smokes and burns a ton of oil. I dont think it has full compression. It still runs and rides.

you should just get away with new piston, rings, and a cylinder hone, Id throw in a new timing chain and cam gear just for saftey though.

[motojunky]

so my room mate has a 1994 XR 250. We are thinking about rebuilding the engine.

What parts are necessary to replace on a rebuild?

what is the general cost for us to do it on our own VS having the shop do it?

thanks in advance for any help you can provide!

I'll let you know in a week or so:

[lanz]

Guy on ebay sells k&L timing chains for $55 made by borg warner. siriusinc is seller. Bought several from him. How is the cam and lifters?

[motojunky]

If the bottom end is shot, scrap it!

I'm not sure I agree with this. If you can do the other labor yourself, you're out ~$140 for a rod kit and less than that to have someone rebuild your crank. Add crank bearings (along with your top end cost) and you'd probably be in the ballpark of the cost of a used mystery motor from Ebay (OK, maybe a bit more), and you'd know it's fresh and will last a long time.

If the transmission has issues too, then yeah, it could get too expensive quickly. I guess it all depends how nice the bike is otherwise and how attached you are to it.

[KI6HNB]

Who is good with rebuilding heads and porting them at the same time? And how much would a rebuilt and ported head cost?

[JoeBlow Kokomo]

I'm not sure I agree with this. If you can do the other labor yourself, you're out ~$140 for a rod kit and less than that to have someone rebuild your crank. Add crank bearings (along with your top end cost) and you'd probably be in the ballpark of the cost of a used mystery motor from Ebay (OK, maybe a bit more), and you'd know it's fresh and will last a long time.

If the transmission has issues too, then yeah, it could get too expensive quickly. I guess it all depends how nice the bike is otherwise and how attached you are to it.

XR'sOnly charged me about $400 to rebuild the crank from my 350. Carillo rod and new bearings. Complete upper and lower gasket sets are more than $100.

Couple of machinists (guys here on TT that have other posters verifying their good work) said they would do it for less than $300. FWIW

Agree with motojunky, I hated spending the $$ on an old bike, but now I KNOW that it's all new and solid, everywhere. I ended up with about $750 in the motor but it needed a lot of little things once it was opened up. Lots of little parts add up. But lots of new little parts add up to a much more reliable bike too. I paid a guy I know $300 to do the work.(whole bike, not just motor - he earned 1/2 of that getting the swingarm off IMO! ) Would have been at least double that to have a dealer do it.

Ought to be good for another 20 years now.

[lanz]

I dont see the value in porting a XR head myself. Porting is mainly for high RPM which XR's are the standard for their low end grunt. Throw on a bigbore, maybe a bigger carb, open pipe and ride the bike. If you want to rip go get a CRF250R or a YZ250F. They come stock ready to turn 12,000 rpm! My 2 cents.