2003 cr85 engine rebuild question

[undergroundart]

I got the crank out today and found some long scratches in the bottom of the crank case and some scratches towards the top where the cases meets the cylinder. should I be worried about these? im thinking about trying to lightly buff them out. what do you guys think

 

[undergroundart]

 

[Awk08]

i'd knock any high ridges off and not worry about any gouges.

 

[harley1-5]

looks to me like debri may have been I there at 1 time

 

[undergroundart]

got it all buffed out. actually looks pretty good.

 

[rich1]

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Looks like the bearings were moving in the cases when hot . This can happens when someone replaces bearings with out heating the cases or a bearing that locks up. I would put some green locktite on the cases before installing the bearings.

 

[undergroundart]

shoot, good idea. but I got the new crank and bearings in already. just about ready to to seal up the cases. just wanna triple check that I got the tranny all right. it kinda all fell apart when I split the cases

 

[rich1]

shoot, good idea. but I got the new crank and bearings in already. just about ready to to seal up the cases. just wanna triple check that I got the tranny all right. it kinda all fell apart when I split the cases

If the bearings went in tight ,you may be ok . If they were just a bit loose then they will move when the cases heat up.
This sort of problem happened on Kart roadracing motors that turned 12,000 to 18,000 rpm I used to build , I always used green locktite to prevent it.

 

[undergroundart]

they were real tight going in. im pretty sure the scratches are from when the crank bearing failed, but loctight would have been some cheap insurance either way

 

[undergroundart]

if my cases use a gasket do I still need to glue them together? or is the gasket enough

 

[Blaaster]

If it is a YFS 200, you need no gasket between the case halves, only a smear of bonding agent.

 

[Awk08]

2003 cr85 engine rebuild question.....

thats a good question for us non gasket using blaster guys, i'd think a very light coat of case bond would not hurt a thing.
did you detect any during the disassembly ?

 

[Blaaster]

Oops, did not spot the Honda tag.

 

[undergroundart]

a trusted race dad says that if theres a gasket that they don't need to be glued. the gasket that I took off was stuck on pretty good in a few spots. but I don't think it was glued. got the cases together. now to wait for my cylinder to come back from porting and see if I put it all together right

 

[undergroundart]

this things making me mad now. checked and made sure it shifted thru the gears before I put the cases together but now it doesn't. tore it apart, then put together. cant quite figure it out. shifts fine till the cases are like a 1/16 apart, then it s like something is getting pinched. does it matter which side I put the tranny in first? I ve had the closest success starting with in the case with the clutch

 

[rich1]

this things making me mad now. checked and made sure it shifted thru the gears before I put the cases together but now it doesn't. tore it apart, then put together. cant quite figure it out. shifts fine till the cases are like a 1/16 apart, then it s like something is getting pinched. does it matter which side I put the tranny in first? I ve had the closest success starting with in the case with the clutch

Are you sure you did not leave a thrust washer/shim off the mainshaft ? Did you use a Honda brand case gasket or aftermarket. May be wrong thickness ... measure with dial calipers .

 

[undergroundart]

ya I ve checked what I have with the diagrams from partzilla that show each part of the tranny. I m pretty confident I have that right. the gaskets came from hot rods with my crank

 

[rich1]

ya I ve checked what I have with the diagrams from partzilla that show each part of the tranny. I m pretty confident I have that right. the gaskets came from hot rods with my crank

Still sounds like its binding on the main shaft ends . If it shifts fine till the cases are put together, and the gasket is too thin it will bind. Is the crank turning freely ? The only other thing I can think of is a trans case bearing that is not seated, but you did not replace them right.

 

[undergroundart]

sh*t, no I didn't replace those bearings. they probley moved a lil. i cant believe i didn't think of that.

 

[undergroundart]

just had to tap on the tranny bearings a little. put it all back together and it all spins and shifts decent. spent a ton of time doing thins but I really did learn a lot. im not nervous about tearing into the bottom end at all anymore