Jerky 1st gear in low rpm

[mikw73]

^ Great instructions on rear brake use!

It took me about two months after starting the rear brake plus clutch technique before I could do full lock turns confidently. I wasn't riding real frequently, though. Of course, I stopped practicing for a while after that and got worse at it, but I've had three parking lot sessions in the past month and am pretty sharp now.

So mines the diamond?? It does nothing like any of that stuff and I lug its @ss up hill at idle or punch to 10k and it's smooth and never misbehaves.

Mine's just a little lumpy as it goes from idle up to 5K, and only if the throttle is pretty far open. As a result, I just use first almost exclusively with the clutch in the friction zone and modulated with brake. It makes for smooth riding, but my mpg in traffic probably suffers a little. Letting the clutch out all the way in first gear is something I only do if I'm trying to ride real fast.

 

[FinalImpact]

My only gripe is the throttle chop when coming down from >6k and getting back on the gas. As such and depending on my mood I may have it in 1st at 9 to 11K coming out of the corners vs being in 2nd and having the transition trashed by the chop.


FWIW: I rarely slip the clutch to take off. At the time the clutch hits the sweet spot I'm just off idle and letting it pull from 1000rpms. I know the clutch can handle being slipped from 3k (or more) to take off but its just not my style. That's not say i can't or don't but typical just don't have a need to unless wishing to play and be aggressive.

On one of the streets headed home its up hill at a fairly steep grade. Auto's progress a car length at a time and stop. It's about 1.25miles. Its rare I put my feet down and I keep about a cars distance behind the vehicle in front of me. Oh - and seldom will it rev past 2k as you CAN ENGAGE the clutch off idle on a hill and not kill it or lurch. Idle is 1250. . .

Blah blah blah opcorn:

 

[pookamatic]

My only gripe is the throttle chop when coming down from >6k and getting back on the gas. As such and depending on my mood I may have it in 1st at 9 to 11K coming out of the corners vs being in 2nd and having the transition trashed by the chop.


FWIW: I rarely slip the clutch to take off. At the time the clutch hits the sweet spot I'm just off idle and letting it pull from 1000rpms. I know the clutch can handle being slipped from 3k (or more) to take off but its just not my style. That's not say i can't or don't but typical just don't have a need to unless wishing to play and be aggressive.

+1

I don't have any real problems with low speed lurch. If it starts to buck, clutch it and smooth it out, shift if necessary.

But yeah, coming off throttle then getting back on... PUNCH. I'm trying a new method where you twist the throttle up to right before you would normally get the buck, and wait momentarily for the engine braking to slow the bike into the matched throttle position.

 

[FinalImpact]

So what came of this?

I will say that when going down a very minor incline it does a little bit of jerking sensation. Its hardly noticeable but its there on occasion. I'm roughly at a slow walking speed when it happens. Pulling the clutch and coasting is a quick fix however I have also slipped the clutch/added throttle & brake all at the same time but honestly why bother when going down hill?! Its just easier to pull the clutch in and coast! Oh - and from the sounds of it, its my chain going slack and then taught as I run it on the loose side.

 

[chunkygoat]

Sorry if this is a repeat post - I didn't read through every reply....

I have an 08 s2 with 25k miles on it - and I can tell you I just had that issue. Low rpm chatter, slight slippage. Even holding the RPM's steady, the bike would either lag or lurk forward.

Its your sprockets and or chain. I just replaced my sprockets and it cured the low rpm chatter/slippage. Sounds to me like the exact problem I had, the sprockets were worn and the chain was slipping.

New sprockets and chain are in line from the sounds of it. No biggie.

 

[FinalImpact]

Sorry if this is a repeat post - I didn't read through every reply....

I have an 08 s2 with 25k miles on it - and I can tell you I just had that issue. Low rpm chatter, slight slippage. Even holding the RPM's steady, the bike would either lag or lurk forward.

Its your sprockets and or chain. I just replaced my sprockets and it cured the low rpm chatter/slippage. Sounds to me like the exact problem I had, the sprockets were worn and the chain was slipping.

New sprockets and chain are in line from the sounds of it. No biggie.

but this represents a "worst case" chain //sprockets as those were well beyond service use IIRC. . . . Was it the "single tooth" remaining on the front? IMO - not comparing apples to apples.

So what came of this?

 

[Marthy]

If you have a PCV add some gas (3-5%, more if needed) in the lower rpm under 15% throttle, that should smooth thing out a bit. That fix most of the problem I had around 4K on my ride.

 

[fyrebug]

didn't notice all the replies here. thanks everyone!

nothing has come of this. I read the first few replies and just figured i was wrong. talked to the machanic when I got my rear tire changed as it was OEM at 17k km... NEEDED IT. and he rides an r6 and just said these machines want to be going a little faster and just just pull the clutch in a bit but that it's normal.

the chain and sprocket are original, could be them.. might not be.

when I put the bike up on center stand to oil the chain the rear brake drags. somewhere else in this forum I read a little drag is normal and that it will always touch a bit.

so I'm not really sure what to think of that. my definition of 'drag' might not be right. it's a rubbing sound that happens in a certain section of the rotor, not the entire time, and it doesn't stop me from turning the wheel.
this is when cold though, I didn't know to try after a ride. I can do that tonight.

 

[greg]

how many rotations does the tyre make if you spin it around by hand?

should be around 1-2 with a decent spin. Less than half a spin and I'd start checking if things are binding.

 

[fyrebug]

less than half a spin.

but I need clarification on binding. I'm not convinced this is out of the norm as it's new to me.

there's a rubbing sound from the pad as I turn the wheel, the pad is touching, but it's not stopping me from turning.
the rubbing sound is just a light sound of the 2 touching, and it sounds like scratching.

if I push down on the rear break the piston moves in/out by about 1mm-2mm? the pad itself does not retract with the piston. I assume that's the design of them and that the pad is just meant to be pushed away from the rotor through the spin of it?

thanks

 

[FinalImpact]

Cruise about a mile at 20+mph and stop without using the rear brake. If the rotor is too hot to touch, the drag is an ISSUE and would be wise to be addressed.

This appears to defy my faith in mechanics, but aligning my rear wheel better dropped the rotor temperature. Its really fixed by the bracket to the axle so IMO it should not have changed it but it "appears to have changed it".

The spin test also includes drag of the gear box, chain condition, and chain alignment. These can be misleading. Heat tells a story and there shouldn't be much. Mine is basically "air" temperature when touched after after stopping with the fronts.

besides - a tiny bit of drag isn't going to cause this jerkiness you started this thread with but should be addressed if its an issue.

 

[mikw73]

Has anyone suggested checking the throttle cable slack? Mine started feeling jumpier about two years back, and taking out throttle cable slack, chain slack and practicing slow riding in parking lots helped a lot. Since then I've added throttle tamer and adjustable levers and it's even smoother. In a few more miles I'll do a TB sync, I think. Maybe ECUunleashed at some point.

 

[mikw73]

Along the same lines of thought, I saw one of those crazy motorcycle control videos with an FZ6!

FZ6