losing compression

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Smellybumlove

losing compression

Post by Smellybumlove »

yep its been drinking fuel at about 2 litres every 70kms and fouling plugs, had it looked at and i have been told its losing compression, its only got 13000kms on it so im a little pissed about that :( .

but the good news is that a big bore and higher compression kit only costs around $100 including labour, this will solve the above issues and increase the power.

now the question is, with a 2-3mm bore increase, how much cc will it be now?.

oh and im running 8g rollers, take off is good but it revs so much up to 60mph and goes fairly slowly after 30mph that i wouldnt recommend it, think 10g is the best comprimise.
BGK
Member
Posts: 244
Joined: Thu Sep 27, 2007 8:07 pm
Location: Minneapolis

Re: losing compression

Post by BGK »

35km/liter of fuel is pretty good fuel efficiency. It's very hard to believe you were getting better than that before. Also, reduced fuel mileage and fouling plugs is usually not a matter of low compression. I'd say your autochoke system is stuck on. If it was low compression (easily tested with a compression gauge), 100.00 is pretty good for a replacement even though that many kms is on the low side for being due for a replacement. I wouldn't think twice at needing one at 16-18,000 kms so you are not that far off. Usually you'll have symptoms of hard starting and a significant drop in performance when the wear of the cylinder is too great.
Smellybumlove

Post by Smellybumlove »

hmm maybe your right, i guess its just that im filling up more often as it can only hold over 2 litres of fuel!.

if the choke is stuck on then that might explain why its much quicker when its cold and slower from the lights when its warm?!.

oh and how long doe sit take for a clutch to wear in, been riding for 70kms on this new one now an di still feel its slipping from the lights.
BGK
Member
Posts: 244
Joined: Thu Sep 27, 2007 8:07 pm
Location: Minneapolis

Post by BGK »

Smellybumlove wrote:hmm maybe your right, i guess its just that im filling up more often as it can only hold over 2 litres of fuel!.

if the choke is stuck on then that might explain why its much quicker when its cold and slower from the lights when its warm?!.

oh and how long doe sit take for a clutch to wear in, been riding for 70kms on this new one now an di still feel its slipping from the lights.
The scooter being quicker when cold could be from several factors. As the variator/belt/clutch system gets really hot it doesn't performa as well. It could be from the autochoke stuck on, but hard to say without checking it out.

A clutch shouldn't really have to wear in. But if someone did the job with greasy hands it will slip. Also, if the bell was well worn and only the clutch was renewed it could slip just as bad as a worn clutch. It would be like getting new brake pads on a car without the drum or rotor being resurfaced. you can maybe get away with it but if there is significant wear on the metal surface it won't help much.
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