cr80!

[5horsebriggs]

I don't know, I saw the box said .5 but what do I know

 

[MB165]

.25 mm is .010"
.50 mm is .020"
.75 mm is .030: and so on.
you can go 2mm over with wiseco.


If the cylinder is worn the exhaust side of the piston skirt could be broken off. You will have good compression but it wont run. Happened to me back in the day about three times. you'll be running along and its like someone hit the kill switch.

 

[5horsebriggs]

.25 mm is .010"
.50 mm is .020"
.75 mm is .030: and so on.
you can go 2mm over with wiseco.


If the cylinder is worn the exhaust side of the piston skirt could be broken off. You will have good compression but it wont run. Happened to me back in the day about three times. you'll be running along and its like someone hit the kill switch.

Yea but I have no compression

 

[Justpassedu]

5horsebriggs i like that ride , real nice. I know you were in my thread a few days ago , did you need parts from a mb165 motor bc i have that one from my bike , maybe i can help you out ?

 

[Harleys Papa]

.25 mm is .010"
.50 mm is .020"
.75 mm is .030: and so on.
you can go 2mm over with wiseco.

Ah I wasn't even thinking about metric conversion :doah:

 

[Boomstick]

Punch it out to a 500, should be easy, right? :wink:

 

[5horsebriggs]

5horsebriggs i like that ride , real nice. I know you were in my thread a few days ago , did you need parts from a mb165 motor bc i have that one from my bike , maybe i can help you out ?

Haha no thanks the parts are for the cr engine

 

[5horsebriggs]

Found some things that ruined my day I got 1 piston with bits of metal on the top, one piston ring stuk in the groove and one thats fine, a conn rod with lots of play, side to side
Any up and down, I'm gunna fix everything I know is wrong

 

[5horsebriggs]

Sent from my iPhone using Tapatalk

 

[mipowdercoater]

The bits on top are most likely the bottom end. I would split the case and replace the bearings and have some one true the crank.

 

[bigrob]

Thats to bad , but 2 strokes are like that , I have a matching one from the suzuki I blew up.lol
Fortunatly they are relativly easy to rebuild

To bad you sold your lifan clone , you prob could have made it fit in the cr frame

:thumbsup:

 

[5horsebriggs]

Yea the Bearings are Bad on the rod and I wouldnt put the clone, it would ruin it! Lol

 

[Tom S.]

I wouldn't rush to tear the bottom end apart just yet. The rod on an engine like yours can feel loose even when everything is fine. How does the cylinder head look? If the big-end bearing failed badly, the piston could touch the head in the squish band area. The clearance there is really tight. Does it look like they touched? Try to post a clear photo, and a sharper pic of the piston, too, please. To feel play in the big end bearing, you need to hold the rod as straight as possible while you pull it up and down. Unless the failure was catastrophic, one that's quite worn will still only produce a barely perceptible clicking noise or feel. To check this, it helps if you rotate the engine to TDC so you can get a good grip on the rod, and then lock the engine in place by putting it into gear and having someone step on the brake.

How To Check Rod Bearing Play On A Motorcycle - YouTube

 

[5horsebriggs]

The shrapnel on top of th piston makes me think the bearing, and I thought I defiantly felt alot of play but ill go check again

 

[5horsebriggs]

Yup I need a New crank And Connecting rid which mb165 has but for the amount if money I need to spend I might just put a blaster motor in it

 

[Boomstick]

The bike looks like it's worth doing right.

Get a new (or rebuild) the old crank, clean up the cylinder, new wrist pin, new rings, replace ALL bearings, and you should be good to go.

It PROBABLY wouldn't hurt to do a lot of carb work & tuning just to make sure you're not running balls-to-the-wall lean.

 

[Boomstick]

If you swap a different motor into there & cut/weld motor mounts, you're making a $100 monstrosity.

Keep it original.

 

[MB165]

The bike looks like it's worth doing right.

Get a new (or rebuild) the old crank, clean up the cylinder, new wrist pin, new rings, replace ALL bearings, and you should be good to go.

It PROBABLY wouldn't hurt to do a lot of carb work & tuning just to make sure you're not running balls-to-the-wall lean.

i agree....
keep it, make it a project. its the
second year honda made a 80. just about everything is the same as the 1980, and some with the 82. they arent too rare but a complete bike is. just do a little bit at a time as the cash comes in....

 

[Tom S.]

If you swap a different motor into there & cut/weld motor mounts, you're making a $100 monstrosity.

Keep it original.

+1 :thumbsup:

 

[5horsebriggs]

i cant come up with the money for parts, i cant have to spend alot of money, how long do crank bearings last? i can offord piston and rings but i will be 450 into it and i still might end up selling it