Help with Rebuild

[figueiredoj]

Hi.

I'm currently inspecting my 02 CRF450R engine, already measured the valves, rocker arm, removed the cylinder head, cylinder and Piston.

 

My exhaust valves are ok and they don't need replacement, but the intake ones do (planing to send the head to cut the valve seats on the intake side and install a kibblewhite ss kit).

 

 

 

After removing the cylinder the cross hatch looked ok, but noticed that there where some light vertical scratches, can't feel any of them by hand.

 

 

I attempted to measure the cylinder bore and the piston with a micrometer caliper but I'm not sure about the right way to do it.

 

Inspected the connecting rod (its a prox one) and it doesn´t have any vertical play, just horizontal play.

I'm not sure if it needs replacement or not, but I think since it has horizontal play it does.

BTW I can take a photo of the wrist pin to show you guys, it doesn't have any scratches felt by hand.

Hope that you guys can help me, since this is my first engine rebuild.

Best regards here from Portugal.

[Diggla117]

If that's the original cylinder then I'd replace it with a new one and eliminate taking the chance of it being ovaled all together. Plus you won't have to order a hone if you don't already have one.

The crank should have VERY minimal play side to side if any but none up and down. If your questioning it mise well spend the cash and get it right while your there. Hope that helps

Edited August 3, 2014 by Diggla117

[figueiredoj]

If that's the original cylinder then I'd replace it with a new one and eliminate taking the chance of it being ovaled all together. Plus you won't have to order a hone if you don't already have one.

The crank should have VERY minimal play side to side if any but none up and down. If your questioning it mise well spend the cash and get it right while your there. Hope that helps

 

I was thinking the same on the cylinder, its better not to take the risk.

Planing of ordering a oem top end kit with cylinder.

I think that the play on the crank isn't normal it doesn't have any vertical play but the side by side play can be felt.

It's better to do a full engine rebuild to have peace of mind, after all then I can run it without worries  ?

What do you think about the cylinder head? Will it be ok if it just has the intake seats done and the new valve kit put in ?

Thank you for your quick response  ?

Edited August 3, 2014 by figueiredoj

[Diggla117]

To each his own BUT

Me I like building my motors to rip as hard as they can while staying completely reliable and staying running pump gas.

If you have a factory cam or a stage one the I'd get a complete set of SS valves put in

Stage two or three cam and I run TI valves.

You can prob get away with just replacing the intakes if you wanna save money for now. And yeah you need to get all the seats cut.

I always but 13.5 pistons kits back in unless that person is tight on cash and unsure of their crank but if your gonna replace the crank then I recommend a 13.5 compression piston. I like CP pistons, best in the game. That's what I would do but like I said to each his own. And no problem man

Edited August 3, 2014 by Diggla117

[Diggla117]

Second thought- you have a 02 which the stock cam is about the same as a stage two but that motor came with a like 11.1 piston ratio or somethin low like that. You would feel a HUGE difference with a 13.5 piston and would really wake that motor up with that factory cam... It's the best factory cam Honda has put in these bikes for power

[figueiredoj]

I ordered a complete oem top end kit (cylinder and piston kit with gaskets) for 362.43€ with shipping and import taxes included.

Here in Portugal Nikasil cylinder replatings are 300€+, oem cylinders are way to expensive to buy new here in dealers, piston kits also 150€+ w/o gaskets so I think that this deal is pretty awesome.

I'm gonna contact the seller and try to get a 04 piston that has 12.5:1 compression with the kit (02 oem is 11.5:1).

Hopefuly he might do the same price  ?

What do you guys think of wiseco bottom end kits?

Sorry for the newbie questions...

 

BTW my bike is this.

 

Maybe I'm gonna do a rebuild project when the parts arrive to keep you guys updated  ?

Again thank you very much for your help  ?

Sorry if my english is a bit wrong.

Edited August 3, 2014 by figueiredoj

[Diggla117]

Wiseco cranks are a BIG no no. It's normal for wiseco cranks for last 20 hours run time then fail.

Yeah I guess 12.5 would be better than what you had.

Not sure how much that translates to but you did checkout eBay right? Anyways yeah let us know and keep us updated

[figueiredoj]

Hum, didn't know about that...

And Hot rod cranks, are they any good?

If not I'm going oem.

[Diggla117]

Hum, didn't know about that...

And Hot rod cranks, are they any good?

If not I'm going oem.

Hot rods are great! I prefer them over OEM but oem is good also if not just as good.