Rear tire chirps on deceleration

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Scalded Ape @ 04

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This is probably a common trait of a shaft driven motorcycle? But when I am really ringing the 1200's neck in the top of say 2nd gear, then abruptly let off the throttle. The rear tire suddenly begins to hop, chirp and almost lock up unless I roll back into the throttle or of course clutch. This can get a little hairy going into a sweeping curve. Is this common or a possible mechanical issue? If not, any advice on better technique is welcome.
 
I've been riding my 2007 since I bought it brand new in 2007 and the only time that EVER happened is when I screwed up and dropped a gear I shouldn't have dropped. (And for the record, that's only when I dropped to 2nd or 1st when I thought I was a gear higher.)

It has never, ever happened simply by letting off the throttle. If it is with you, you've either got something bad wrong or you're riding like a complete imbecile.
 
it's kind of a trait of every bike i've ever had that had any power. i could ride my rgv250 like that but not the gpz1100. chain or shaft. hell i wouldnt run an evo softail into a corner hard in 2nd and chop the throttle.

its why alot of bikes come with slipper clutches now.
mostly to save the um well...back to you parminio.
 
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I think it's called torque vs. traction. my 85 will do that, my xr650l will do it too. brothers busa not so much. it has a slipper clutch to prevent the idiot from running into a cornre at 8 grnd and chopping the throttle causing wheel lockup and eminent death. Leaving me to take care of his nasty little offspring.
 
I thought this was a nicer group of people. I'm not asking everybody to be soft, but I wasn't expecting to be referred to as an imbecile or an idiot. Hell my Honda Shadow will even do the same thing just not as severe. I guess I was just looking more for a technical explanation as to what's going on. Also, with any bike there is a learning curve until you get to know the ins and outs of it. It was a one-time learned mistake that didn't land me in the ditch or dead.
 
i wasn't calling you an idiot. my brother certainly is. he actually rode his bike through his garage door. my guess is between the shaft an agressive riding style and always poor traction due to the lack of sticky rubber you're experiencing wheel lockup. im sorry if my post came off that way. i personally rode a gpz1100 into a isuzu npr truck, a suzuki vx800 into the side of a minivan, a cb550 into the side of a caddillac allante and last but not least a kdx200 into the side of freddy rivers barnstable county cop car on main street. soooo not much room here for insults.

personally i think if you could back a vmax into a corner you da man.
 
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The bike is moving faster than the transmission is. Thats why its happening. Same with chirping tires under acceleration. In that case, the car is moving slower than the transmission. Two things happen....skid or chirp. When I used to motocross, I use to drop that extra gear to get the rear tire into a slide around turns. Of course once I was out of the turn, I could goose it and I was back in the power curve. I was on dirt of course so no noise.
 
What kind of tires are you running? Any mods done to the bike, carb work, a 4-1 exhaust....etc?
 
A few mods, UFO 4/2/1 exhaust, sean installed a muscle jet kit, has a power commander, few other things and just general maintenance, valve cover gaskets and new F seals. It has a kenda Kruz 150🤣
 
I'm afraid that with my (can't resist the twist riding style) if I had a better tire such as a shinko I may snap the driveshaft or worse, round off a gear dog or something. The DD grabs very hard.
 
The DD mod will eliminate the designed in factory slippage. Especially if you eliminated the dampening plate arrangement at the back of the basket.
 
This is what's happening.

You are 'really ringing the 1200's neck in the top of say 2nd gear' by which you mean near maximum revs?
At those revs the engine is sucking in some 90 litres of air per second.
You shut the throttle which closes the throttle butterflies which in turn causes a partial vacuum in the cylinders.
This will try to prevent the pistons from going down the bore.
Get a bicycle pump, put your finger over the end and try to extend the pump. Not easy eh?

That is what is happening inside the engine.

You also have the gearing to consider
In first gear you will get the least revolutions per x revs of the engine i.e. there is high leverage, good for driving off and going up steep inclines. As you go up the gears this leverage reduces until you get to top which is good for maximum speed.

By closing the throttle in second there is a high leverage and because of the vacuum described above the engine can't rotate quickly enough to match the speed of the rear wheel.
This will cause the wheel to slow down to match the engine revs and if the wheel speed is less than the road speed....you know what happens.

If you are doing this on a regular basis then you will be putting forces through the power train that it probably wasn't designed to accommodate.
At some stage something inside may well say 'sod that' and break.

Solutions:

i) Don't snap the throttle shut but roll it off. IMO what you are doing is a bad riding technique as you are unsettling the bike which at some stage could end in tears.
ii) Allow some slippage in the transmission by a light pull on the clutch. DO NOT pull it right in, you are only releasing it sufficiently to allow a little slippage to allow for the difference between engine and rear wheel i.e. effectively a manual slipper clutch.

I would not advocate the second option as it is a very fine line between getting it right and getting it wrong.

Hope that answers your question.
 
This is what's happening.

You are 'really ringing the 1200's neck in the top of say 2nd gear' by which you mean near maximum revs?
At those revs the engine is sucking in some 90 litres of air per second.
You shut the throttle which closes the throttle butterflies which in turn causes a partial vacuum in the cylinders.
This will try to prevent the pistons from going down the bore.
Get a bicycle pump, put your finger over the end and try to extend the pump. Not easy eh?

That is what is happening inside the engine.

You also have the gearing to consider
In first gear you will get the least revolutions per x revs of the engine i.e. there is high leverage, good for driving off and going up steep inclines. As you go up the gears this leverage reduces until you get to top which is good for maximum speed.

By closing the throttle in second there is a high leverage and because of the vacuum described above the engine can't rotate quickly enough to match the speed of the rear wheel.
This will cause the wheel to slow down to match the engine revs and if the wheel speed is less than the road speed....you know what happens.

If you are doing this on a regular basis then you will be putting forces through the power train that it probably wasn't designed to accommodate.
At some stage something inside may well say 'sod that' and break.

Solutions:

i) Don't snap the throttle shut but roll it off. IMO what you are doing is a bad riding technique as you are unsettling the bike which at some stage could end in tears.
ii) Allow some slippage in the transmission by a light pull on the clutch. DO NOT pull it right in, you are only releasing it sufficiently to allow a little slippage to allow for the difference between engine and rear wheel i.e. effectively a manual slipper clutch.

I would not advocate the second option as it is a very fine line between getting it right and getting it wrong.

Hope that answers your question.

And here's the TL;DR of that

what you are doing is a bad riding technique

Also, to address this:

I thought this was a nicer group of people. I'm not asking everybody to be soft, but I wasn't expecting to be referred to as an imbecile or an idiot. Hell my Honda Shadow will even do the same thing just not as severe. I guess I was just looking more for a technical explanation as to what's going on. Also, with any bike there is a learning curve until you get to know the ins and outs of it. It was a one-time learned mistake that didn't land me in the ditch or dead.

You came in here saying you were "ringing the 1200's neck " thinking everybody would Ohhhh and Ahhhhh over your riding prowess.

Nobody dumps the throttle. Nobody. Well, there is one exception: when a car just pulled out in front of you and you're doing everything you can to stop.

Racers don't do it.

Cops don't do it.

Anybody that's ever taken any kind of riding class don't do it.

Sorry about your "feelings", but slamming the throttle shut at max RPM on a Vmax is a really good way to wind up dead. One of these days doing that shit, that tire isn't going to hold up, it's going to completely lose grip and go out from under you and you're going down.

Hard.
 
This is probably a common trait of a shaft driven motorcycle? But when I am really ringing the 1200's neck in the top of say 2nd gear, then abruptly let off the throttle. The rear tire suddenly begins to hop, chirp and almost lock up unless I roll back into the throttle or of course clutch. This can get a little hairy going into a sweeping curve. Is this common or a possible mechanical issue? If not, any advice on better technique is welcome.
Well today you win first prize for asking the most stupid qestion of the day...thats just my opinion..
 
Friends don't let friends ride-on Kendas. Try Shinkos for a lower-price point with traction. Did you see that deal on-here, a front & rear for $133?

Also, unsettling the bike's dynamic attitude by chopping the throttle like you describe isn't anything which you want to-do, regularly. Consider taking the MSF 'Better Biking' course, that's what it used-to be called. It's for a rider with time under his belt, to learn more about how to use available traction, the use of countersteering, emergency braking, etc.

In riding there are several groups of people. One is the show-off, who has to behave like an idiot because they crave attention, "look-at me!" They cut-between rows of cars, even at-speed, they never ride at or below the speed limit, they weave in and out of a column of traffic, etc. I'd generally refer to them as 'accidents waiting to happen.'

The rider who leaves room between his bike and the vehicle in-front of him, and who watches his mirrors, stopped at a light/traffic control device; who gaps himself in traffic, who allows the aggressive vehicle operators to go by, or who moves-away from them; a person who travels with the flow of traffic, and who isn't constantly grabbing a fistful of throttle or brake, is someone who isn't likely to be surprised by ending-up sliding across the road sans bike, wondering, "how did I get here?"

Practice smooth riding inputs to the throttle and the brakes, choose lines which avoid the oil-soaked pavement at intersections, check your mirrors constantly, scan farther down the road, to notice other drivers' behaviors, all those people suddenly braking and changing lanes may be avoiding a piece of furniture which fell-off someone's vehicle, or a carcass of an exploded truck tire, lying in the road.

It doesn't take much to upset our rides, after-all, they're inherently-unstable. They fall-over if you stop and don't support the stationary bike. Hit a patch of sand, gravel, anti-freeze, oil, coolant, ice, or any-other traction-eliminator, and you could be that guy sliding-across the pavement, sans bike.

Reg Pridmore was a very-successful rider, he won championships in Superbike, and he operates the CLASS riding school. Here's a great example of what the careful rider gets to witness:

 
'Fraid is disagree, at least he has had the balls to recognise something wasn't right and try to find out why.
What would be stupid would be if the advice given was ignored.

Agreed.

Give the guy a break.

Nothing wrong with your bike.
A sticky tire would be less prone to break loose but more prone to break parts.
Max Midnight gave you the best advise. Better throttle control or clutch control can help eliminate this.
 
And here's the TL;DR of that



Also, to address this:



You came in here saying you were "ringing the 1200's neck " thinking everybody would Ohhhh and Ahhhhh over your riding prowess.

Nobody dumps the throttle. Nobody. Well, there is one exception: when a car just pulled out in front of you and you're doing everything you can to stop.

Racers don't do it.

Cops don't do it.

Anybody that's ever taken any kind of riding class don't do it.

Sorry about your "feelings", but slamming the throttle shut at max RPM on a Vmax is a really good way to wind up dead. One of these days doing that shit, that tire isn't going to hold up, it's going to completely lose grip and go out from under you and you're going down.

Hard.
Not trying to be rude in return, but literally everyone on here talks about "ringing the neck of the vmax" popping wheelies and all kinds of aggressive riding. So I am not trying to impress anyone, just another guy on a forum with nothing better to do such as yourself lol.
 
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