bike keeps wheeling

[stranger12]

Hi All,

As I am honing my skills and pinning the r6 harder to learn how to do a hard start without wheeling, I am finding it extremly difficult to keep the front down while accelerating .

It could be well r6 is too powerful which is unlikly or simply could be the suspension setting are not set correctly so the rear compress very quickly and thus wheelie.

don't get me wrong I like it to be wheelie happy but this is now too much . is that how it is or rather suspension problem ?

Also I am not light , I am around 105kg so think that loads the rear when I moved further back and hug the tank with my knees.

Is that right ?

Also I am getting headshakes or tank slapper ( not that extreme) most of the time when pinning it which I can't work out why .

Any help is much appreciated.

thanks
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SV650 Red
R6 Red

[el_oso]

slip the clutch better.

don't pin it so much coming out of corners, roll on the throttle instead.
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Duke 390
Previous: '05 XR125L | '96 XJ600S Diversion |'05 Suzuki GSXR1000 | '05 Honda CBR125-R | '97 YZF 600R Thundercat | '11 Honda CBR250
Car: Jeep Wrangler 4.0L

[stranger12]

sorry I was referring to straight line.

if I let it slip then I can not get to 60 quick enough. for instance I see figures saying the 0-60 on r6 is under 3 sec but I can't even get it close to 4 I think because it keeps popping up.

I got 3.6 on my sv650 as it was not mad and it didn't used to pop up as much as my r6 .

the r6 is stronger but yet slower.

so either setup or simply me not having the skills hence why asking for opinion and how to go about it .

also do you have any suggestions re the front end shaking on hard acceleration ?
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SV650 Red
R6 Red

[el_oso]

I was refering to a straight line.

You still need to slip the clutch better. To get the most accelleration out of the bike you need to have the revs in the range where the bike makes the most power. IL4 600's have little power down in the low end of the rev range so you need to keep the revs high. You can control the amount of power going from the engine to the back wheel by slipping the clutch. When you get it right your front wheel should just start to get light.

The reason why the SV650 was quicker is because it's a v twin with more power in the lower end of the rev range. For this reason there is no need to slip the clutch so much to get the most useful amount of power out of the engine.

In summary you skills are lacking. If you want to get better then you need to practice that clutch control. This will burn through your clutch pretty damn quick though and it will take a long long time to get it that much better. Even some F1 drivers still struggle with their starts and they have launch control.

what do you mean by the front end shaking? on a straight or out of a corner?
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Duke 390
Previous: '05 XR125L | '96 XJ600S Diversion |'05 Suzuki GSXR1000 | '05 Honda CBR125-R | '97 YZF 600R Thundercat | '11 Honda CBR250
Car: Jeep Wrangler 4.0L

[MaybeGuy]

check the sprocket sizes. If you have a smaller front/larger rear you'll get what you describe.

I can't remember what stock size is, it's been a while since I had an R6.
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Blue_SV650S wrote: it was a sh1te wheelie, but it proves that he can get it up in 3rd and can do angles. In summery, mattsprattuk is a gobby little sh1tebag, dopehead tw4t, but sadly for all of us, he probably isn't THAT full of sh1te!!
Kickstart wrote: Hi I tend to agree with Matt. All the best Keith

[RhynoCZ]

[gavcarter]

The trick is to accelerate just hard enough to slightly lighten the front end.
Accelerate a bit more and the front tyre looses traction, causing your mild wobble as it skims over the road surface - is likely to go into full on tank slapper if you hit a bump
Accelerate a bit harder than that and you start to lift the front wheel and do a wheelie.....

From a standing it works like this.....

Rev bike and hold revs at X rpm ( where ever the power band is - google a standard dyno run for you bike and find where the power peaks)

When at X rpm ( see above^ ) let clutch out quickly and smoothly until the bike has just enough power to launch and NOT flip up into a wheelie.

From this point as the weight transfers back to front wheel, increase throttle to full and let clutch fully out simultaneously, again you want the most power without bringing full wheel up.

Or that's whats worked for me anyway, G or some other track nut will probably have a better understanding or description

[G]

The issue, I would suggest, is with your right hand - you need to practice a little finer control.

It does take a bit of practice to get used to the front just skimming the ground.

As you weigh a fair bit, getting your weight forward makes sense too.

Early R6s do tend to shake their head - I'd expect it on bumpy roads accelerating hard. Consider a steering damper.

Using the clutch to keep the front down but the speed up is one method that can be easier to use on a sports 600.

[Kickstart]

[stranger12]

looking at below

i think by power band we are referring to where the max torque is not hp, right ? so based on below mine is at around 10K .

Are you suggesting I should rev it to 10K in a stand still and then slip the cluth ? I do it to 4k but that ia not where the peak torque is .

https://www.frederickbecker.com/graphics/2005_yamaha_yzf_r6_dyno.jpg
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SV650 Red
R6 Red

[Ste]

4k!?!?! That explains everything.

Rev the bike properly and slip the clutch more.

[Kickstart]

[Old Git Racing]

If you want to get the acceleration figures published by Yamaha do it like they tested it. Bounce it off the rev limit and slip the clutch to keep it in the sweet spot (over 10k) with the wheel skimming the road. Do that 20 times then fit a new clutch.
As for it head shaking I would check the rear sag, if there is too much add some spring preload. If you can't get the correct sag because you are too heavy then it needs a stronger spring.

OGR
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2022 Tiger Sport 660 2019 Street Twin 2003 K3 gixxer 1000 1998 Srad 600 track hack

[lihp]

Head shake isn't uncommon for quick sports bikes not fitted with dampers.

[gavcarter]

[gavcarter]

by the sounds of it you are doing this
https://www.youtube.com/watch?v=4pdJIcOqCjg

You should be doing this (2.20)
https://www.youtube.com/watch?v=XDMivP58Smw

Couldnt find a decent launch of a sports bike that was any help - it all seems to be nooby power wheelie stuff

[G]

You don't need peak torque.

You probably do need more than 4k, however. If you hold it open at 4k, likely you won't have enough power to lift the front, then you'll have too much.
Because the R6 has a fairly peaky feel to the delivery, it can take more skill to keep the front down and get maximum acceleration just winding the power on as opposed to using the clutch to moderate power.

By 2005 I thought they'd calmed the R6 handling down a bit.
Should it come with a damper? If so, does it? Around that sort of time, most bikes were starting to come with a damper as standard because they didn't want to get tone the handling down, but also didn't want riders thrown off.

[stranger12]

mine isn't as bad as that first one. I lunch much quicker.
I practiced on the way to home with 8-10k and it is way quicker but an animal as it is hard to slip the clutch .

it seems like a truck is hitting me at the back when I am about to lunch . It is the beginning and have to learn but also noticed shortly after the small of my clutch so won't be doing it to often .

maybe I start at 6kish for normal city drag racing and only use 10k for big cars like other they I smashed an m5


thank you for your suggestion . It helped quite a lot

so in a way even in races, they slip the clutch for a while , right ?
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SV650 Red
R6 Red

[G]

On a small 2 stroke (ie 125), I would typically hold the revs high and slip the clutch to keep the revs up so maximum power is getting to the wheel.

On a sports 600, your issue shouldn't be needing more power - you already have enough to wheelie, which is more than is needed. You may however gently use the clutch to keep the front down.

If you get used to winding the power on appropriately, you shouldn't need to use the clutch after 6/7k and should still get just as good acceleration without burning through clutch plates.

In a track racing environment you only significantly use the clutch that one time in the race, so it's less of an issue, but if I could, I'd still get it fully let out and use the throttle alone.
But there is a video somewhere of me doing three wheelies in first gear at Lydden (short track, so heavily downgeared), before giving up and using second. That sort of thing doesn't get you the holeshot.

[Old Git Racing]

In a race they bounce it off the rev limiter and abuse the clutch. doesn't matter if they have to put a new clutch in every meeting. Look at some U tube stuff from the R6 cup or even a modern BSB supersport race.

OGR
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2022 Tiger Sport 660 2019 Street Twin 2003 K3 gixxer 1000 1998 Srad 600 track hack

[trevor saxe-coburg-gotha]

[RhynoCZ]

When I want to do a fast take off, I pre-rev it between 8k-9k rpm, just because the old zxr engine is not that fast to be revved that high up from idle that quick. When I actually take off I give it even more revs, let the clutch slip so I get just an slight front end lift off, then when the wheel touches the ground again, I push it to around 11k where I shift 2nd, 2nd to 3rd and then 4th, 5th, 6th happens at 13k rpm, sometimes even further.

I tried it yesterday, worked as always.

https://i970.photobucket.com/albums/ae184/RhynoCZ/ZX7R/temp_zps8f29b932.jpg
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'87 Honda XBR 500, '96 Kawasaki ZX7R P1, '90 Honda CB-1, '88 Kawasaki GPz550, MZ 150 ETZ
'95 Mercedes-Benz w202 C200 CGI, '98 Mercedes-Benz w210 E200 Kompressor

[stranger12]

but to be quick you need to push it to where the max hp is .

so if you image the max torque is at 11 and you change at 11 then in the next gear you will start off in a lower range thus less torque where as if you red line then you start off in a higher range in the next gear thus more torque.

so looking at the chart I posted earlier and also below , I think i should aim to start on 10k and shift at around 13k. my bike can go up to 15.5 but the hp is going downward so even though in the next gear I will be higher up in the range if I shift at 15.5 , I would loose time as from 13kish to 15.5 my bike is loosing power hence slower .

I am pretty confident this is correct and happy to be corrected if someone thinks otherwise

https://www.frederickbecker.com/graphics/2005_yamaha_yzf_r6_dyno.jpg
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SV650 Red
R6 Red

[G]

For shifting, you want the maximum amount of time at max power.

Typically this means shifting near the red line as the power is starting dropping.

Imagine a mountain and cutting off the top. If you change to soon, you'll be cutting a chunk off the side and the average power in that chunk will be lower.

[Kickstart]

Hi

Peak torque is where you will have the most thrust in any particular gear. Peak power is where you will have the most thrust at any particular speed if you gear the bike to be doing that rpm at that speed.

Based on that graph you would probably be changing up around 14k (the exact rpm would probably vary on which gear you were in).

All the best

Keith
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