Honda 2-Stroke Bottom End Rebuild, Part 1

Dirt bike bottom end rebuild. Part one of a complete motorcycle bottom end rebuild. 2001 Honda cr250.

Category:

Autos & Vehicles

Tags:

• motorcycle
• dirt
• bike
• bottom
• end
• lower
• rebuild
• crank
• bearings
• honda
• cr250
• cr
• 250
• crankshaft
• cr250r

[2fstmotox]

how do you take the bolt there at 1:21 when we do the clutch just spins

[myblazeofglory]

Use a clutch holding tool on the clutch to keep the clutch from spinning. If you look close you can see the tool on the clutch and wedged against the bench. It's like a big pair of vice grips.

[wotracing22]

Ok. Picked up the head today. $225 all said and done (honing and piston kit). Lucky its a two smoke and didnt cost an arm and a leg! Slowly getting it back together and noticed i need another gasket for the vforce reed valve. Darnit! Any recommendations to break it in when its ready? Also the joint where the exhaust pipe and muffler meet leaks oil all over. Id rather not buy a $50 aluminum (T&M designs) coupler. Do you have this problem? Help is greatly appreciated. Thanks!!!

[myblazeofglory]

I just bought a replacement rubber sleeve for the exhaust..doesn't leak anymore. Just don't get the bike too hot and don't go too hard for an extended time, get it hot then let it cool for the first few hours ride time.

[wotracing22]

I just dropped off the top-end to Engine Dynamics. Its going to run me $200 to have the cyl. re-honed including the piston kit. Mike (the owner) said it was good timing because the piston was worn and showed some signs of siezure. He'll check to see if the head is warped also.

Question- What is your oil to fuel ratio? I was running 32:1 Honda HP2 Blue bottle stuff. Also what oil do you prefer for the gearbox?

Cool man- Thanks again for all the knowledge and documentation!

[myblazeofglory]

Nice! I run Bel-Ray H1R Synthetic and I love the stuff. It's more expensive, but you don't have to mix quite as much...It recomends 40:1. I run Bel-Ray gearsaver in the gear box. I'm planning on a full top end next season..re-plate etc. I appreciate the feedback and info as well.

Glad I could help..feel free to drop by the site etc. and talk shop anytime:) blazeofgloryoffroad . com

[enginemaster8]

what kind of pressure plate is that?? O.O

[bintwert]

you could have done one thing different;y,to remove the gear off the right end of the crank,leave the clutch basket on and put a washer between the basket and the gear and the loosen the bolt,the way you did it could cause some damage

[Liberalsuck100]

@crf100person Dude i could rebuild your bike for you in 25 minuets.

[killer4life1000]

it looks like youve done this b4

[crf100person]

my brother just ran his yz125 with gas that he thought had oil in it but it didnt and now its messed up. a mechanic said it would need to be replated and a new piston, and i think he said that would be $1000 if they did everything, and if it needed a new crank rod it would be like 1300-1500..... doesnt this sound high to yall? but we would put the piston in ourselves

[ed563]

@ 1:20 WTF were you doing to the clutch basket... destroying it?

[RonniesGarage]

@DSMFORLIFE92 typicly side to side is ok but extreme movement in any direction means bad bearings pull your motor aprt pull the crank and im almost positive the bearings will need to be replaced. and besides most people only replace the bottom end when it goes and by then its a 50/50

whether or not the motors salvageable.

[RonniesGarage]

@maxx268 neutral must be between 1st and 2nd!

[maxx268]

i have a 1986 cr 125 and im rebuilding the entire motor, i just got finished installing the gear shift drum and i noticed that neutral is all the way down and 1st gear through 5th is up. is that ok to run it like that or does neutral have to be beetween 1st and 2nd gear. can you please respond back to me on this.

[Mbomben]

Do I need to remove all the kick start gears, shift pawls, and what not if I am just replacing the Left crankcase? My crankcase is majorly cracked right between the flywheel and sprocket so I need to replace it because its too big of a crack for JB weld.