SK5 - Query re top speed and restriction

You could always dyno it instead of relying on anecdotal evidence.

Mine (K6) was dyno'd at about 68/69 bhp.

Originally Posted by yorkie_chris

Screaming like you hit a rev limiter or something?
Your mate BS'es about there being "much more to go" above 135mph. Pointy has 70bhp, 72 if you put full system and air filter on one.
Yes the acceleration is reduced above about 115mph.

If you still think yours is particularly short of poke, swap bikes with your mate and see what his does.

He said he had an indicated 135 out of it and although it was slowing up there was a little left to go. I know how mine feels at 115 and I doubt I could hit 135. Luckily we both are regulars at track days so have the opportunity to reach these speeds.

Neither of us are bothered by speed, going really fast or anything like that, it was just he mentioned that he had hit that speed and it made me think about my bikes capabilities.

Originally Posted by yorkie_chris

Surely it would still be mapped to deliver the correct fuel for say half open SDTV so even if you wired the SDTV full open or removed the butterflies it would run lean as hell?

Maybe. I think it is dependant on exactly where IAP is being measured. If air pressure is measured downstream of the throttle plates then those secondary plates shouldn't matter to mixtures. They might as well be the main throttle plates and there would be no reason to change the ignition/injector map except perhaps to prevent circumvention. It is just the SDTV map that needs to be changed.

If IAP was measured anywhere else then it would matter, but SDTV is sometimes disabled on full power bikes to de-limit it (seems to be more of a DL thing) in the bottom end and lower gears and on the DLk for top speed without upsetting mixtures except at the bottom end - that could have something to do with IAP sensor response at high manifold pressures.

I have no idea, but hopefully you see what prompted my earlier question.

well mine is a k6 15000 miles myns 33bhp and myn will get 115mph with a good winding it up but takes foreva to get theere i am 11stone myns completly standard

[yorkie_chris]

Originally Posted by MattCollins

Maybe. I think it is dependant on exactly where IAP is being measured. If air pressure is measured downstream of the throttle plates then those secondary plates shouldn't matter to mixtures. They might as well be the main throttle plates and there would be no reason to change the ignition/injector map except perhaps to prevent circumvention. It is just the SDTV map that needs to be changed.

If IAP was measured anywhere else then it would matter, but SDTV is sometimes disabled on full power bikes to de-limit it (seems to be more of a DL thing) in the bottom end and lower gears and on the DLk for top speed without upsetting mixtures except at the bottom end - that could have something to do with IAP sensor response at high manifold pressures.

I have no idea, but hopefully you see what prompted my earlier question.

I see exactly what you mean, some of the racers disable the SDTV entirely, someone is making a "box" to fool the ECU into thinking the SDTV is present so it can be removed. Normally they remove the butterflies entirely but leave the spindles.

What actually is the point of this thread?

The only way to tell if you bike is restricted is to top it out, but you don't seemed to be bothered about speed anyway so whats the biggie?

Originally Posted by jacksuzukisv650

well mine is a k6 15000 miles myns 33bhp and myn will get 115mph with a good winding it up but takes foreva to get theere i am 11stone myns completly standard

I will be at 100 from standstill in a matter of seconds - so that must be good news.

Originally Posted by Girth

What actually is the point of this thread?

The only way to tell if you bike is restricted is to top it out, but you don't seemed to be bothered about speed anyway so whats the biggie?

I dont want a restricted bike, so want to make sure it is unrestricted. My friends comments regarding his top end made me think about the bike, and having posted up it hs gone from there.

so what is the top speed of a resricted and unrestricted sv.........my bike gets to 115 in no time then slows alittle while it gets to 125, theres still something left, just waiting for a nicer day (and a bigger set of kahonars), oh yeah all this happens on my private track, wink wink

[yorkie_chris]

I've had 135 indicated on my naked one. You should get 140 indicated on the fairy ones.

Restricted most I ever saw was just under 100, mostly 95 though, and I would generally crawl under the paint on the tank and try that daily!