any chance it's ok - overheated & kept running

looking for some expert opinions before i start tearing into my bike.

i did my 1st hare scramble today.

overtemp light came on early in the race due to pileup in the rocks.

i pulled over a couple of times to let it cool. one time briefly, and another long enought for the light to come off - which came on soon again after getting back on it & continuing.

decided i wasn't quitting & ran the whole race with the overtemp light on.

did a quick ride in the yard after the race & bike seems like it has a new off idle weekspot.

coolant was down a bit, but not too bad. topped up before test ride.

i need to wash the bike & pull the valve cover to start.

any opinions on what i'm gonna need at a minimum.

prob need new rings. hoping my recently rebuilt by eddie bottom end isnt toast.


was it pushing coolant out of the catch tank?

yeah it was. coolant level was down a bit after the race.

there was also a distinct knock when running it harder on open uphills.

just wondering if i need to tear this thing all the way down.

over heating affects the piston/cylinder more than the rest of the motor.

thanks eddie

i guess the knock was probably piston slap due to an over-heated, over-expanded cylinder?

what would you do? pull cylinder, measure & inspect top end and replace as needed was going to be my plan. and check side play of con rod.

prob gonna need a new 94mm kit

if its hurt you wont need to measure anything to see it.

why did it overheat REHH I mean in the slow stuff I can see but after that ??

did you fit a fan to it ?

I'm assuming the we're talking about the E in your Signature

why did it overheat REHH I mean in the slow stuff I can see but after that ??

did you fit a fan to it ?

I'm assuming the we're talking about the E in your Signature

it's my S model. all my fault, as i took the fan off years ago & sold it...

still run the thermostat too.

rarely have over-heating problems where i normally ride. didn't think about the possibility of over-heating yesterday until the light came on - yep...too late.

the course was constantly changing - it would open up for a little bit, then back to tight stuff.

oh least i had fun

i'm going to look for a used fan, a higher pressure rad cap & make sure my rads are clean(not obstructed with dirt).

i removed the cylinder today and everything looks good by eye.

haven't measured anything yet, but nothing obvious.

eddie - can you get rings & circlips for the 94 mm JE piston?

if the rings are not removed from the piston, is it still not a good idea to re-use them?

yes,i can. you should replace them.

ok...i'm second guessing my initial findings...again

there is light scoring on the cylinder walls on the front & rear.

there's also possibly some wear on the piston skirt.

i think the cylinder is ok. i'm just not sure if it needs a hone or just some scotch brite.

there's a taper on the piston skirt diameter. it measures approx. 2.799" @ the bottom of the skirt and approx. 2.793" @ approx. 1 1/8" up the skirt.

manual says to measure piston skirt .06" from end of skirt.

i tried to show some pics of that

here's the pictures. my appologies for the poor quality.










can you feel the marks with your finger nail?

no eddie. still feels smooth. definitely not as bad as last time before you honed it for me.

any input eddie? excuse my persistence.

worse case scenario, i send the cylinder to you for honing & buy a new piston or piston kit.

scotch brite and run it.

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