I just bought two Snoscoots for my boys. I have been through them and both are more or less the exact same. One is a 88 and the other a 89. The 89 flat out rips. The 88 seems to start out strong but then it seems like the power all of a sudden flattens out not like the 89 which pulls to top end. I checked the carbs to see if the mains were different but both carbs are identical and set the exact same.
The 88 has a B8HS plug and the 89 has a BR8HS plug which i don't think should make a difference.
I noticed the 88 had a intake leak around the read cage where a little oil/gas was slowly seaping out. I fixed that but it did not make a difference. I did a compression test on both. The 89 was 120 hot and 125 cold. The 88 was 90 hot and 112 cold. I cannot seem to find a compression spec anywhere.
If i lift the back end and WOT it seems to stay strong all the way through and it seems to get past this flat spot.
Any other ideas ? Thoughts ?
The 88 has a B8HS plug and the 89 has a BR8HS plug which i don't think should make a difference.
I noticed the 88 had a intake leak around the read cage where a little oil/gas was slowly seaping out. I fixed that but it did not make a difference. I did a compression test on both. The 89 was 120 hot and 125 cold. The 88 was 90 hot and 112 cold. I cannot seem to find a compression spec anywhere.
If i lift the back end and WOT it seems to stay strong all the way through and it seems to get past this flat spot.
Any other ideas ? Thoughts ?
You can try replacing the fuel pump. I've had a lot of trouble with the pump not keeping up with the fuel demand on WOT. I've chaned several of them and my top end comes back strong..... 
I was guessing the drive belt????
I just changed the fuel pumps around to see if that was it and no change. New plugs gapped properly no change. The funny thing is when i lift the back end off the floor and pin it it seems to almost clear out and the flat spot dissapears, until i put some weight on it the flat spot is there. It has to be either low compression or maybe a clutch issue. Low compression would effect the top end for sure. Its funny how when idling it doesn't seem as strong as the 89.
I have new clutches coming for both of them so that will take care of the primarys. Strange. Cold compression is up at 112 psi. I looked at the belt and it looks pretty good although i didn't measure them yet.
I have new clutches coming for both of them so that will take care of the primarys. Strange. Cold compression is up at 112 psi. I looked at the belt and it looks pretty good although i didn't measure them yet.
staggs65
Moderator
seems to me like that would be the difference
I just got back from riding with my boys on the lake. I noticed if i rode down a boat launch ramp it had it full power and if held to the bar it would actually accelerate to top speed and stay there until i let off the throttle and then it would have the flat spot again. Would compression do this ? Seems strange. I really wonder if this is a compression problem or some weird fuel/oil problem. I'll have to measure the oil pump to and see if it putting out the appropriate amount. Clutching needs investigation as well, LOL
PZ 1
Member
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- Mar 12, 2005
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Yup.staggs65 said:
There is definately a problem there, no need to look any further. It may not be all the problem, but whatever is causing the low compression needs to be fixed, so do that first.
sounds like a dirty clutch or weak spring in the primary.