Topic: what is this lever ?

[scunny]

this is on a race 500/4 and it's the extra lever on the clutch.
my first thought(yes I know, bad idea) is it a choke lever, but why would you put it up there on a race bike, when the original is on the carbs.
 

[750goes]

No idea what thats for...could it be an extra clutch lever or clutch adjuster ? cant see where the cable goes.. but it seems to follow the clutch cable routing ??

[dafrpa]

Those look like later pumper carbs, could well be a choke lever.

[Dusthawk]

I've seen this kind of lever a couple of times, one was a choke, the other was a valve release for higher compression engines used in race applications, easier for starting.

Peace,

Jeff

[cb650]

I've seen this kind of lever a couple of times, one was a choke, the other was a valve release for higher compression engines used in race applications, easier for starting.

Peace,

Jeff

Was my first thought. 



                     Terry

[Raul CB750K1]

I've seen this kind of lever a couple of times, one was a choke, the other was a valve release for higher compression engines used in race applications, easier for starting.

Peace,

Jeff

I second that. Actually, my Sanglas bike have a decompressor you must use if you don't want to have a bent connecting rod when cranking the engine with the starter motor.


Raul

[Terry in Australia]

I think a "valve decompressor" would be a major engineering feat for a 500/4, and probably unnecessary anyway, so my money's on a choke lever. Cheers, Terry.

[Raul CB750K1]

I think a "valve decompressor" would be a major engineering feat for a 500/4, and probably unnecessary anyway, so my money's on a choke lever. Cheers, Terry.

Even when you are running high compression pistons and you got rid of the starter motor?

[Terry in Australia]

I think a "valve decompressor" would be a major engineering feat for a 500/4, and probably unnecessary anyway, so my money's on a choke lever. Cheers, Terry.

Even when you are running high compression pistons and you got rid of the starter motor?

Yeah Raul, Rex Wolfendon's CB750 based 140 Bhp 1100 CC race bikes don't need one, why would a 500 four? Big long stroke singles like your Sanglas need 'em, but not small capacity (by cylinder volume) multi's. Cheers, Terry.

[Raul CB750K1]

I think a "valve decompressor" would be a major engineering feat for a 500/4, and probably unnecessary anyway, so my money's on a choke lever. Cheers, Terry.

Even when you are running high compression pistons and you got rid of the starter motor?

Yeah Raul, Rex Wolfendon's CB750 based 140 Bhp 1100 CC race bikes don't need one, why would a 500 four? Big long stroke singles like your Sanglas need 'em, but not small capacity (by cylinder volume) multi's. Cheers, Terry.

Yep, that makes sense. You are compressing just one cylinder at any given moment, as opposed with singles with a comparable displacement...

Raul

[Mark M]

Well it looks like the throttle lever off a Suffolk Punch Lawn Mover to me, but my guess is
it's a Doohan style thumb operated rear brake lever.

[eldar]

Well I had an old beat up yamaha twin I think that had a decompression lever. It as a 500 or something like that. I used it as a kind of brake.

[Noel]

Is it hooked up to anything? It may just be borrowed clutch lever from a dirt bike or something, with the decompression lever not accomplishing anything.

Otherwise, why not just trace the cable and find out where it goes?

[puppytrax]

My money says a front parking brake...for victory burnouts...   

[Terry in Australia]

I bet it doesn't get used much...........

[MRieck]

Well it looks like the throttle lever off a Suffolk Punch Lawn Mover to me, but my guess is
it's a Doohan style thumb operated rear brake lever.

My thought also though...on a drum brake....yikes! It would take 4 thumbs to work.