GSX-R fast idle question

[jonoZRX]

Hi all

On my '00 GSX-R750 the rear slides round a lot when I brake. It seems to be the main area that I'm losing time on the really quick guys, so I'm keen to get it sorted. I want to try other options before buying a slipper clutch, so I'm thinking about just turning the fast-idle lever on. I've done a quick google search and didn't find what I needed, so my questions are:

> How does it actually work? It appears to connect near the idle screw, but what is the actual mode of action?
> Will the bike run rich and explode if I leave it on? Or is it just like turning the idle right up?
> Would it just be easier to turn the idle screws right up?

Any help will be greatly appreciated... unless you tell me to blip the throttle more, in which case I will hunt you down.

[jasonbw]

Might want to grab Zeno's opinion by posting in his forum too, suspension has a lot to do with (everything to do with) keeping the tyre on the ground. What sag (rider and static) are you running at the back?

[jonoZRX]

I actually think suspension is a different issue in this case. It was all spot-on last time I rode it, and I think the sliding was simply due to compression lockup. I'm now about 6kgs lighter, so the previous suspension settings are probably meaningless. I've still got about another 6kgs to go (got real fat after my crash), so it'll be a work-in-progress and I'll have to play with it a lot.

I might pop it in his forum anyway though, just in case.

EDIT - maybe not. I can't find where I recorded my previous sag settings, and they'll be completely different now. Not sure if he'll be able to help if I can't give him any information :p

[tempest161]

use the 'manual' slipper clutch... index and middle fingers left hand (i only use those 2)! you can ride around it or most certainly learn to use it to help turn the bike into the corner.

[jonoZRX]

use the 'manual' slipper clutch... index and middle fingers left hand (i only use those 2)! you can ride around it or most certainly learn to use it to help turn the bike into the corner.

Already doing that one! It helps a lot, but I'm thinking that upping the idle speed would make it even more effective.

[tempest161]

it could but it may cause other issues. my idle sits at 2 - 2500 depending on my mood, helps me maintain higher cnr speed. thats just my preferance, everyone is different. when you out at the track next? try it and see!

[jonoZRX]

try it and see!

That's what I'm going to do, but I just want to make sure that it won't affect the fueling (fast idle on the early 2000's model GSX-Rs is on the handlebar like a choke) and cause problems due to running rich - hence the question on how it actually works :)

If it will potentially damage the bike I'll just have to go and get some skills instead of looking for an easy mechanical fix :p

[jasonbw]

Maybe pop a PM to Dungbeetle, if it does run rich he'd likely know (and you would too by ruined spark plugs so good move on asking:))

[Kat00]

I think your referring to cold and warm idle but not sure how the 00 work

Witn the latter Gixxers on starting they will idle slightly higher when they are cold, similar to a choke, I'd imagine it richens it up a bit so I wouldn`t be messing with the cold idle screw but uping the warm idle would have no fowling effect.

There is a 00750 manual on the RATs server, if ya want it PM me and I'll give you the password

[jonoZRX]

Maybe pop a PM to Dungbeetle, if it does run rich he'd likely know (and you would too by ruined spark plugs so good move on asking:))

Yeah, that's the reason for the question. I got a four-stroke so I wouldn't have to worry about plugs anymore! I probably could've worded the initial question better though. I'll shoot him a PM and see if he knows what I'm rambling about.


think your referring to cold and warm idle but not sure how the 00 work

With the latter Gixxers on starting they will idle slightly higher when they are cold, similar to a choke, I'd imagine it richens it up a bit so I wouldn`t be messing with the cold idle screw but uping the warm idle would have no fowling effect.

There is a 00750 manual on the RATs server, if ya want it PM me and I'll give you the password

Cheers Kat00, I've actually got a service manual. The '00 is injected but it has a manually operated lever on the left clipon, similar to a choke. The service manual says it opens a throttle valve to increase the idle speed, but I'm not sure if this will make it run rich because I know SFA about fuel injection.

[zRoYz]

Friend used to do what your asking increase his idle to about 2500-3000rpm which will help stop compression slides. I don't know the lever you are talking about as not up on gixers but I wouldn't use the lever if it is a fast idle choke type system (bike would run rich). I would be inclined to just up the idle screw try 500rpm at a time & test effect.

[Dunno]

I remember hearing that Franky Chili ran his bike sitting on 4000rpm at idle for tha same reason. Stopped compression lock up & helped maintain corner speed.

[Stu23]

I upped the idle on my R6 sits about 2.5k now, as you say helps out when screaming through the gearbox, but also, good old fashioned clutching down with throttle blips to balance out engine and rear wheel speed helps too....just crashing down the box will have the rear skipping and jumping like a wild thing :) good to watch though

[schoops]

Don't know whether your '00 750 is the same, but on the 05 1000 and it has an adjustable throttle stop (a knurled bolt you can adjust by finger) on the throttle actuator on the left side of the carbies. By winding it in you are just opening the throttles slightly, so it's not affecting your fuel mixture.

[muzz]

as far as i know injected bikes dont have a choke as such ,and the fast idle lever is just that ..a fast idle ...inrichment is done by the ecu. to back this up my tl and my sp1s fast idle cable goes to the throttle butterflies.

[Wiccad]

My previous ride was a 2000 KY GSXR-750 (note, their was also a 2000 J to which this does not apply being a carbied bike). The fast idle leaver on the left handlebar operates a cam that holds the mechaical butterflys open a crack. I had mine tweaked to work as a sort or cruise controll for doing long trips and the bike would hold 115kph on the flat in 6th.

On the KY this is a perfectly acceptable method of temporarily raising the idle rpm as it effectively holds the throttle on a fraction. It does not open an idle curcit or give the ECU any special signals. So far as the ECU is concerned the throttle is slightly open is all. Latter models from 2002 for the 750, 2001 for the 600 and 2003 for the litre bike use a different throttle body air bleed and a variable position sensor as is the case on my current 2001 (K1) GSXR600.

Their is of course the idle adjuster screw mounted next to the coolent bottle but that is hard to get at while riding.

If you need a factory manual for this bike let me know, I have it on PDF.

[jonoZRX]

Thanks for the advice guys. It seems that a few people are doing the same thing, so I'll give it a whirl next time I get out to the track. With my other bike I've found that simple adjustments like this can often give noticeable benefits.


My previous ride was a 2000 KY GSXR-750 (note, their was also a 2000 J to which this does not apply being a carbied bike). The fast idle leaver on the left handlebar operates a cam that holds the mechaical butterflys open a crack. I had mine tweaked to work as a sort or cruise controll for doing long trips and the bike would hold 115kph on the flat in 6th.

On the KY this is a perfectly acceptable method of temporarily raising the idle rpm as it effectively holds the throttle on a fraction. It does not open an idle curcit or give the ECU any special signals. So far as the ECU is concerned the throttle is slightly open is all. Latter models from 2002 for the 750, 2001 for the 600 and 2003 for the litre bike use a different throttle body air bleed and a variable position sensor as is the case on my current 2001 (K1) GSXR600.

Awesome, thanks for that. I was trying to trace the cable and was pretty sure that's how it was acting, but I'm mechanically inept and wanted to check with someone who knows what they are talking about so I didn't kill it by running rich. I've also had the same answer from two other Y-model owners on another site, so I think it's confirmed.


Their is of course the idle adjuster screw mounted next to the coolent bottle but that is hard to get at while riding.

Yeah, that makes it a little hard to play with and compare results during a session :p