Head Pitting?

[swett]

:bang: :| I need some help fellas! My 87CR80 started making noises on deceleration. Couldn't really tell where it was coming from so I pulled the top end down. Piston, cylinder top bearing and every thing within specs. The head however looks like someone destroyed a piston or sucked in some trash and got caught in the quench..coupled with the engine cases having marks that look like the connecting rod had beat up the cases a lil bit. (Connecting rod thats on now has no marks.) Do I need a new head or might i be able to save it? I know I'm getting a new piston and all that but I don't want to have to buy another head if I don't have to. Also the cyl. has a pew score marks but nothing i can even catch a fingernail in..plating is fine. I'm kinda at a loss, this being my first 2stroke and all.

Thanks for the help.
Swett

 

[swett]

P.S. Where is a good place to order parts from for this bike?

 

[rob129]

Service Honda, they will save you quite a few buck versus the local dealer!!!!!!!! Go here to inquire about prices.
http://69.213.66.54/TSWEB/Default.htm
If it wont let you clink on connect, wait a few minutes and windows will ask you if you want to upgrade or download some file, I forget the name...click yes, you will need it to get in. After that is said and done it will let you click on the connect button. From there sign in as WEB, the password is GUEST (it is case sensitive). From there it will bring you to blank page with weird tool bars on top. Click on file and open files I think it is...motorcycle...the CR80 and then the year. Find what your after, get the part number and put it in the part number block on the inquiry window (its minimized) it will give your the cost and what you save.

Believe me this looks confusing and possibly a big hassle, its not. You'll save $$ in the long run. Local dealers will mark up the prices "A LOT".....some call it price gouging. Good luck man

 

[swett]

:| can anyone help?

 

[reelrazor]

I am going to assume that you are not the original owner of this bike?

Do the marks look old? New? Was that the kind of noise you heard? The ring is okay? Reed valves okay? Sounds to me like something went through your engine, you need to find out a) when b) what, and c) why.

Anything in the intake tract is a suspect, plus any hard parts that are in communication with the crankcase. You say the piston, and wrist bearing are okay. If the ring is still good(no part of it missing) you need to start suspecting the big end rod bearing and the crank bearings.

 

[swett]

No the bike was given to me. The intake tract was fine. bearing runout is within specs. engine ran smoothly. Crank spins freely. No catching or jumping..I do need new reeds though.(just found out upon disassembly.. would that create a thumping and catching noise on deceleration? Ring was still there..end gap was .010"..I believe I'm 3rd owner..2nd owner didn't ride the bike at all before it was given to me. Needed new shifter shaft. I did the change out with no problems. Then disassembled the whole bike to blast and zinc coat and prime the frame...

 

[swett]

Marks on the head are old.. everything else looks new.. i dont know who the original owner is

 

[rickyd]

Is it detonating?? any pitting on the piston??

 

[swett]

Piston was fine. I dont know how to diagnose detonation.

 

[swett]

????????

 

[swett]

Any other ideas? Please help! tired of not riding.

 

[jmics19067]

detonation usually sounds like someone shaking a coffee can full of marbles when accelerating under a load.Other than answering that one question I don't know

 

[swett]

No on acceleration it's fine. Just on deceleration..Thanks for the input though.

Swett

 

[swett]

bump