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nelubian
8th June 2015, 11:53
Hi everyone,

I have started noticing temporary power loss for a 2-3 seconds at 3rd gear at around 40 km h. Initially I thought that was a slipping clutch. I looked at the clutch plates, they didn't seem to be worn. However, just in case I've replaced them with the new ones. Clutch works a bit better, however the power loss persists.

To replicate it following sequence required: 3rd gear (happens at 3rd gear only), speed around 40 km h, slightly uphill, turning the throttle constantly and slowly. At some point power stops increasing. I continue turning the throttle but engine doesn't provide any reaction at all. After 2-3 seconds of the slow throttle turning it harshly rises power. Sometimes I drop throttle and turn it back again to get rid of this power loss, it usually helps.

I wouldn't pay much attention to it. But 40-50 at 3rd gear is a typical speed/gear on a street. And it seems dangerous to have such unpredictable moment.

Any advice of what it could be?

ducatilover
8th June 2015, 21:22
Will it always do it hot or cold?
What revs?
Are you certain it does not do it in 4th and 5th also?

nelubian
9th June 2015, 09:39
Will it always do it hot or cold?
What revs?
Are you certain it does not do it in 4th and 5th also?

I've tried to replicate it yesterday and today morning, but couldn't. It doesn't happen always, I've not found what it depends on (may be temperature, might be weather). It usually happens when the engine is already hot (but once it was just warm). The necessary condition is to ride uphill, I've never replicated it on a flat/downhill. Revs are around 5-6k (mine bike is carb max is around 12k). Tried to get this effect at the same speed at 2nd (more then 8k (out of the powerband) revs and 4th (3k, again out of the powerband) at the same speed, no luck yet.

It has never happened at 5-6k revs at 4th and 5th gear with the same conditions.

ducatilover
9th June 2015, 21:40
Your chain tension okay and no tight spots?
I don't see anything cutting power only in third on one of them, they do have an ignition retard on them but it isn't gear dependent

nelubian
11th June 2015, 09:14
Your chain tension okay and no tight spots?
I don't see anything cutting power only in third on one of them, they do have an ignition retard on them but it isn't gear dependent

A few advices yesterday plus tests and I finally found a reason.

I didn't mention that I am like over 120kg weight + motorcycle 170kg. So I have been commuting on 250cc for a while and never seen any sense in upgrading to the restricted licence(It doesn't allow anything, looks like a typical money generator) and never had experience with powerful motorcycles.

Basically what has happened is: I've been putting on weight since I bought a bike and one day I faced a critical mass of me +bike. And at some point (4-5k revs at 3rd gear, the effect is actually requires a bit less then 5k) simply cannot take me uphill. In such case I simply re-rise throttle or pull clutch slightly and increase revs.

Sorry for stupid question, the problem is ... not big enough motorbike.

ducatilover
11th June 2015, 20:19
Too many pies son :2thumbsup

FJRider
11th June 2015, 20:29
So I have been commuting on 250cc for a while and never seen any sense in upgrading to the restricted licence(It doesn't allow anything, looks like a typical money generator) and never had experience with powerful motorcycles.



Check the expiry date on your learners. Depending on when you got it ... there may be a time limitation on how long before it must be upgraded. (or lost and resit needed)