Idle: Completely different question

[ZeroIndex]

Ok, here's a idle question that is hopefully different to the normal "my bike isn't idling properly help me"

My bike idles perfectly fine at 1250rpm (standard), the problem is, I decided that that wasn't high enough, so I've now put it up to 2500rpm, which is nice (14k redline) and helps with 1st gear wheelies (they don't just slam down when you get off the gas).

Now, some of the other stunts I'm wanting to learn, I need to have the idle around 4k - 5k rpm which shouldn't be a problem... the only problem is the adjuster for my idle is really difficult to get to, probably due to the fact that it's a Yamaha...

The idle currently sits in the middle of the engine, between cylinder 2 and 3 just underneath the airbox. It is reachable by hand, but if your bike is up to temp, it isn't fun to go adjusting the idle cause you'll probably burn yourself.

Now, my question is, either how can I make something that can lengthen the idle adjuster to perhaps next to the left-hand side frame, or even better: can I make a switch type lever that I can adjust so when I flick it, it will just jump from 2k to 4k rpm? If something like that is possible, can someone post some diagrams or a how-to?

Thanks in advance,
ZeroIndex

[xwhatsit]

On a normal carb set-up, you have a choke, which not only chokes the carb intake, but usually provides a fast-idle link. It does this by rotating a cam against the throttle shaft, opening it more.

Is there some way to attach a cable to the fast idle link? Therefore rotating the cam so it opens the throttle, yet not choking the engine up. You could use a normal choke cable and have it up on the handlebars.

Do you even use your choke? If you can get by without it (just having the fast idle may help enough to get it started, especially if you have a pumper carb like me, just twist the throttle a few times to flood the engine before you kick it over), you could take the choke butterflies out, just leaving the fast idle link.

[ZeroIndex]

On a normal carb set-up, you have a choke, which not only chokes the carb intake, but usually provides a fast-idle link. It does this by rotating a cam against the throttle shaft, opening it more.

Is there some way to attach a cable to the fast idle link? Therefore rotating the cam so it opens the throttle, yet not choking the engine up. You could use a normal choke cable and have it up on the handlebars.

Do you even use your choke? If you can get by without it (just having the fast idle may help enough to get it started, especially if you have a pumper carb like me, just twist the throttle a few times to flood the engine before you kick it over), you could take the choke butterflies out, just leaving the fast idle link.

Thanks for explaining how a choke works... I didn't actually completely understand it to begin with (that it was 2 parts)...

Actually, from how you explained it, my choke is already a bit rooted... my choke, when engaged, does the choke butterfly thing, but doesn't do anything as a fast idle link...

Is it possible that the fast idle link has come off the choke cable? if so, if I find that bit and make up another cable that should sort out my problem? Diagrams anyone?

[FROSTY:Me]

Ok dude the EASY solution is to buy a pair of mechanics gloves.They dont transmit the heat fast enough for ya to get burnt winding the idle up.
A more complicated solution would be to remove the carbs. Remove the idle adjuster from the carbs and weld/glue a flexible extention to it --Like on the rf400/bandit 400 suzuki's -then run it out to the outside of the bike.
I usually have the idle on my SV would up to 3 grand for racing

[ZeroIndex]

Ok dude the EASY solution is to buy a pair of mechanics gloves.They dont transmit the heat fast enough for ya to get burnt winding the idle up.
A more complicated solution would be to remove the carbs. Remove the idle adjuster from the carbs and weld/glue a flexible extention to it --Like on the rf400/bandit 400 suzuki's -then run it out to the outside of the bike.
I usually have the idle on my SV would up to 3 grand for racing

Idle extention sounds like the biz... diagram or picture of one Mr. Frost?

[FROSTY:Me]

You will be scratch building a one off. Have a look at your idle adjuster then look at one on a RF400,--Its like a lennth of bowden cable with a knob on the end

[Pussy]

You will be scratch building a one off. Have a look at your idle adjuster then look at one on a RF400,--Its like a lennth of bowden cable with a knob on the end

Bourden cable is fine if you want a thermocouple temperature guage for an idle adjustment.... don't think he wants that

[imdying]

Bourden cable is fine if you want a thermocouple temperature guage for an idle adjustment.... don't think he wants that

You say what now?

[Pussy]

You're quite right. But measuring the pressure of the idle (bourden tube), would be just as impractical

[FROSTY:Me]

BOWDEN cable--the stuff used for throttle cables etc

[imdying]

You're quite right. But measuring the pressure of the idle (bourden tube), would be just as impractical

You say what now? I'm not sure what the point your making is?

[xwhatsit]

Thanks for explaining how a choke works... I didn't actually completely understand it to begin with (that it was 2 parts)...

Actually, from how you explained it, my choke is already a bit rooted... my choke, when engaged, does the choke butterfly thing, but doesn't do anything as a fast idle link...

Is it possible that the fast idle link has come off the choke cable? if so, if I find that bit and make up another cable that should sort out my problem? Diagrams anyone?

It's quite possible that your carbs don't have a fast idle link. Also, it won't take any effect if the idle is already wound way up, as it just turns the throttle shaft to a certain position (say, 2500 RPM) so if the idle is already at 3000 RPM there will be no effect. You can counter this by adding a blob of plastic or something to the fast idle cam to make it lumpier, turning the throttle more. That is, if you have a fast idle link -- I think inline fours are a whole lot easier to start and get running so there might not be a need for it.

FROSTY's solution sounds a lot better; of course you have to turn the idle just like normal, you don't get the fast pull/push that comes into effect at pre-defined positions.

Bowden cable is just the type of cable used in stuff like speedo drives, designed to withstand twisting movements rather than pull/pushing movements such as in a clutch cable. I've seen it advertised on the web alongside normal clutch cable stuff, off the roll. You could get it from a bike shop I'm sure.

[imdying]

No, bowden isn't the roundy roundy type cable, although in this application it will suffice no worries at all.

[xwhatsit]

No, bowden isn't the roundy roundy type cable, although in this application it will suffice no worries at all.

So bowden is the pully pully cable?

Now you've got me in an endless trawl of Wikipedia, starting under `wire rope'

[imdying]

Yep. The Bowden Cable company actually manufactured a special type of outer for pull cables. The difference was the section of the wire used was square instead of round, so they resisted compression better than conventional round section wire type outers, which made them popular for old drum brake race bikes.