Top Speed through gears on a 99 storm

[Firestorm767]

Hi
Does anyone know what the top speed in each gear is on the Firestorm ?
The reason for this is that my bike, a 99 model appears to pull hard to 120mph and then tails off quite sharply. I know that I should not expect more than say a genuine 140ish but I thought the bike would comfortably show 140 - 145 on the clock with a slight tailwind. At the moment once it hits 120 it seems to stop accelerating as if it was restricted and appears to require a lot of road to go any faster. I don't ususally ride flat out so maybe this is this normal ?.

The reason I want to know the speed through the gears is so that I can hold it in 5th to see if it will pull past 120 then.

Thanks for your help !

[Squiffythewombat]

sounds like its been re-geared to me, count the number of teeth on the front and back sprockets!

[Max]

Std gearing, speeds @9500
1...60
2...90
3...114
4...135
5...151
6...169

these are calculated speeds from std size tyres etc.

[mik_str]

Your 99 is obviously not dark blue.... must be yellow or red to be that slow

[Mr Bean]

It should easily reach 140 on the speedo. Mine (red of course) passes the 120 to 140 mark reasonably quickly

Would suspect you're either not getting enough fuel or air in to the engine - blockages in filters, is the throttle opening up fully?Also could be low compression (maybe get it tested) or cam timing out if the tensioners have been replaced and the chain slipped a tooth

In the lower gears you need nowhere near max power to hit the red line.

Good luck

[Squiffythewombat]

In the lower gears you need nowhere near max power to hit the red line.

?????

nowhere near max power to hit the red line??????? red line is maximum rpm?

[Mr Bean]

Squiffy

In the lower gears you don't need full throttle to reach the red line and without full throttle you do not actually hit max torque/power, only the theoretical point.

Max power and RPM are not the same thing

Bean

[Squiffythewombat]

Squiffy

In the lower gears you don't need full throttle to reach the red line and without full throttle you do not actually hit max torque/power, only the theoretical point.

Max power and RPM are not the same thing

Bean

surely max power is the optimum point in the rev range where the most power is produced? this would have no effect on throttle postion, simply the given rpm the engine is turning at?

or am i getting well confused here?

[kevg]

i thought the red line that people speak of is the max revs red band on the rev counter...max power isn't marked and if your on a dyno you can see the power curve drop off before you get to max revs...but the red line is max revs...but it does sound like you have a bike that has had the sprocket sizes changed and therefor won't reach as high a top speed but it will accelerate quicker getting to its top speed.

[Mr Bean]

I should have explained my thoughts better.

Because the point where max power is produced and max revs are quite close I didn't seperate them.

For example, if you rev it to the point where max power is theoretically produced when stationary you only require a small amount of air flow to reach it. You only reach max torque (which is what is actually measured and then a calculation is made to get to BHP) at max air flow, hence my comment about lower gears

Because of other factors - wind resistance etc you need much more power to go from 120 - 140 than say 20 - 40, which is why I made the comment about air flow/fuelling/compression as they all affect max power

I suppose the simplest reply would have been "what revs does it start to tail off"?

[Squiffythewombat]

I should have explained my thoughts better.

Because the point where max power is produced and max revs are quite close I didn't seperate them.

For example, if you rev it to the point where max power is theoretically produced when stationary you only require a small amount of air flow to reach it. You only reach max torque (which is what is actually measured and then a calculation is made to get to BHP) at max air flow, hence my comment about lower gears

Because of other factors - wind resistance etc you need much more power to go from 120 - 140 than say 20 - 40, which is why I made the comment about air flow/fuelling/compression as they all affect max power

I suppose the simplest reply would have been "what revs does it start to tail off"?

Isnt this the reason most dynos have large fans forcing air into the engine to replicate the wind?

BHP is worked out by: the given RPM multipled the given torque divided by 5252!

Lets use this graph (using the red, stock vtr):



From this we can work out the torque using the above equation!

5252 X 101(bhp) / 9000(rpm) = 58.93(lbf)

A lower gear ratio surely shouldnt effect air intake that much as the intakes on the storm are rather restricting anyway?

[LotusSevenMan]

The large fan is normally to aid cooling I think rather than trying to replicate a 140mph + wind!!!!

[Pete.L]

A lower gear ratio surely shouldn't effect air intake that much as the intakes on the storm are rather restricting anyway?

No but it will give you a mechanical advantage.
When you were a kid was it easier to ride you push bike up hill in first gear or top gear? You were still moving the same mass

Pete.l

[Squiffythewombat]

A lower gear ratio surely shouldn't effect air intake that much as the intakes on the storm are rather restricting anyway?

No but it will give you a mechanical advantage.
When you were a kid was it easier to ride you push bike up hill in first gear or top gear? You were still moving the same mass

Pete.l

Sorry pete youve lost me? i dont see the connection between gear ratio and air resistance?

chris - i see! i just assumed those were what the tubes attachted to the front did? (replicating that sort of wind speed isnt that hard provided your pushing the correct CFM surely?)

[firestorm996]

Come to Elvington on the 8th July, and find out what it'll do fer real! ;)