[Gary Smith]

I’ve been running CR80 for 5 years, I love it! I love to get into a rhythm and bang gears. It is not as fast as a 125, but it is a lot of fun and easier on your body.

Gary

Honda CR80 #55

[Gary Smith]

Hi Chuck,

I had this same problem with a CR80  with an 8mm bolt, it was an AMC mount as well. Have you looked at the mounting surface on the motor mount, I bet you see a lot of pitting or gouging where the case meets the mount. What I have done is machine off the gouged area, which was about 1/16 of an inch and add a steel washer that thickness, no problems any more. Another thing to look at is your bolt, do your threads on your bolt end before it goes thru your mount? I buy longer bolts, so the un-threaded portion goes  thru the mount and add a washer or two, and trim off the excess threaded portion.

Hope this helps,

Gary

#55 Honda CR80

 

[Gary Smith]

1st time out with top end, new seals, 30 hrs on crank.

At the end of break in, when I started picking up RPM’s, I first noticed this problem, never experienced anything like this before, never ran this cylinder before. I have had this cylinder for 5 yrs and finally had the juevos to put this massively ported cylinder on a motor. I don’t know if there is a problem with the cylinder and that is why it came as an extra in a “motor package”.

One thing I forgot to mention, the cylinder has an “o” ringed head,  I am experiencing a minor coolant leak on the exterior between the cylinder and head, with no coolant loss and no coolant in combustion chamber.

Gary

#55 Honda CR80

[Gary Smith]

Just checked my wiring, all connections good, with good grounds.

Plug gap .022, spec .024-.028

The motor doesn’t always  break up under WOT, it’s just this RPM range of 10,000-11,000 , it happens sometimes feathering throttle out of corner prior to nailing it. The reeds in the motor had 30 hrs on them, they were damaged, I have changed them with ones that came with cylinder,  I will try them out and see if the problem persists.

If the problem continues, I will check out the electronics, but I doubt if that is the problem, it worked fine before. (every mechanic loves that line) lmao!

I have a kill switch, like before, it worked fine before, I will disconnect it see if it makes any difference.

The motor has run a few what I would call clean laps without breaking up, and when it does, it runs like a raped ape, lots of midrange and top end. I find myself over revving between shifts at 13,500, motor still pulling.

Gary

#55 Honda CR80

 

[Gary Smith]

This cylinder I have came with a motor I bought 5 yrs ago, I thought , what the heck, put a piston in it and see what it does. I did not bother to put new reeds in it. Upon inspection of the reeds, one of them has small break forming on the top edge. When I bought this motor, it came with a set of reeds with a stiffener, I assume these would be high tension reeds. The next time I go out, I will try these reeds, see if it makes a difference, I have an extra reed cage that I have already mounted a set of new low tension reeds.

Gary

#55 Honda CR80

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