Topic: Quarter-turn throttles?

[A Grove]

Title says it all.. What's out there for a reliable quarter-turn throttle that'll work with a 77 cb550's stock carbs? 

Also, is it going to make my throttle pull any "harder" than stock?  Because stock it already seems rather hard.  Other a single or dual carbie that is...

[fuzzybutt]

i'd love to have one on my k4 750. on the other hand i dont want to lose the starter and kill switch in the stock assembly

[A Grove]

I plan to lose them even if I don't get a quarter turn...  One thing you could do is find a low-profile throttlebody and see if you can't use the controls on the inside of the new throttle.  Might be too far in, tho.  And look slightly silly.


Anyone else?

[MCRider]

Title says it all.. What's out there for a reliable quarter-turn throttle that'll work with a 77 cb550's stock carbs? 

Also, is it going to make my throttle pull any "harder" than stock?  Because stock it already seems rather hard.  Other a single or dual carbie that is...

the cafe racer in my avatar used a Tomaselli 1/4 turn quick throttle. Yes, less leverage means more effort. It also means redoing your switch layout. My bike ditched the turn signals, had a little QA50 minibike horn button for the starter, and a british switch for hi/lo and horn. very minimal.

here's an interesting source. http://www.roadandrace.com.au/cat15.htm but you'll have to do your own searching.

[A Grove]

Someone out there must be running one?

[TwoTired]

 
I went out and checked the twist range on my 78 Cb550.  Slightly over 1/4 twist from idle to wide open.  The older 550s had more like 1/3 of twist.

Throttle twist effort is a function of the return spring strength, the slide friction, the cable drag, and the diameter of the twist grip friction surface in contact with the hand.  (unless the the twist actuator has some sort of mechanical cable to twist motion multiplier.)

Are you just trying to avoid the stock controls?

Cheers,

[MCRider]

i'd love to have one on my k4 750. on the other hand i dont want to lose the starter and kill switch in the stock assembly

You can surgically remove the part of the switch housing that the throttle runs in. You won't have recovered all the space, but most of it.

[MCRider]

I went out and checked the twist range on my 78 Cb550.  Slightly over 1/4 twist from idle to wide open.  The older 550s had more like 1/3 of twist.

Throttle twist effort is a function of the return spring strength, the slide friction, the cable drag, and the diameter of the twist grip friction surface in contact with the hand.  (unless the the twist actuator has some sort of mechanical cable to twist motion multiplier.)

Are you just trying to avoid the stock controls?

Cheers,

true you may currently have a 1/4 turn throttle. But using any quick throttle with a larger diameter pull wheel than stock will just make it that much quicker. Hence calling it a 1/4 turn quick throttle becomes misleading.  Also, as you mention, putting a fatter grip on the throttle restores some of the leverage lost to the larger pull wheel. I'll go get a picture and dimensions of the Tomaselli quick throttle i have held back for FreeBird 2. Back in 1 hour or so.

[CrisPDuk]

The throttle tube from a Fireblade will fit inside the stock 550 switch assembly.

It doesn't give you proper 1/4 turn but it is a marked improvement over stock

[TwoTired]

Be aware that the 550 doesn't have an accelerator pump for the carbs.  Sudden and drastic slide opening changes tend to make the engine wheeze instead of accelerate.  (Unless you change the setup to run very rich at all times.)

Cheers,

[voxonda]

I have some that you can attach to the stock assembly. Works great. Here is a picture of the assembly.

If interested PM me.

Rob

[A Grove]

Rob, Please do take some pictures. 

I am looking to get rid of the stock throttle/controls either way.  I wanted to get a shorter throttle throw in the process as the stock throttle has a LONG throw compared to any new/current sportbike, etc.

If I can't find what I'm looking for, chance has it I might need to make my own.  We shall see.

[CrisPDuk]

Yeah, I did notice that TT

My own solution is to not crack the throttle open so quickly

But then my main reason for wanting to reduce the throttle rotation was to stop having to continuously adjust my grip

[MCRider]

The throttle tube from a Fireblade will fit inside the stock 550 switch assembly.

It doesn't give you proper 1/4 turn but it is a marked improvement over stock

That's a good tip, maybe the best one.

Here's what I've got. I thought I had a stand alone Tomaselli Quick Throttle stashed away. but that was a memory from years ago (maybe).

What I did find in a dusty old parts box was a "il comando rapido" quick action twistgrip,


made by "Futura" of Italy. Lord only knows if they are still around.
labeled for a Kawasaki, but I'm betting it'll work on our Hondas. Rather than stand alone, it actually resides tothe right side of the switch assembly, you can see the flange here that fits in the slot of the switch assembly where the throttle pipe used to go.



Then you slip the stock throttle pipe into the converter (see the "V" cutout at the bottom of the middle piece which accepts the pipe throttle)

Pretty cool! And they are set up for both A and B cables. So no matter what ratio your stocker is, this one is quicker.

But I kept looking for the Tomaselli one and almost threw out ... the second Futura one!



No I'm not interested in letting one go, but maybe if you catch me in a weak moment....

PS: Looks like Voxonda may have what I have as well.

But for those of you die hard smokers out there, I also came across... a handlebar mounted cigarette lighter.

[MCRider]

I may have been fixated on Tomaselli, i couldn't find any throtles using that for search. Then i ran across Magura and that rang a bell.
http://www.pingelonline.com/quarter_turn_throttle.htm
also try www.Magura.com
and eBay has lots of throttles on a search for Magura.
My memory was my throttle was sourced from the dirt bike industry and the selection on eBay would indicate that.
There is one for a Drag Bike but searching it I see it is used in the ATV world as a conversion from the thumb throttles.
Gotta go.

[fuzzybutt]

wanna sell one of those throttles? i love the way they will lock into the switch assembly where the original throttle tube went. i want one so i dont have to adjust my grip so much.

[bert96]

 Check this one,

 http://cgi.ebay.com/ebaymotors/CRF50-BILLET-1-4-TURN-THROTTLE-TUBE-CRF-50-XR50-XR-50_W0QQitemZ300096425119QQihZ020QQcategoryZ10066QQssPageNameZWD1VQQrdZ1QQcmdZViewItemQQ_trksidZp1638Q2em118Q2el1247

[MCRider]

wanna sell one of those throttles? i love the way they will lock into the switch assembly where the original throttle tube went. i want one so i dont have to adjust my grip so much.

Sorry I'll be keeping both.

[MCRider]

 Check this one,

 http://cgi.ebay.com/ebaymotors/CRF50-BILLET-1-4-TURN-THROTTLE-TUBE-CRF-50-XR50-XR-50_W0QQitemZ300096425119QQihZ020QQcategoryZ10066QQssPageNameZWD1VQQrdZ1QQcmdZViewItemQQ_trksidZp1638Q2em118Q2el1247

That's nice and for $36 a screaming buy.

[A Grove]

It says for crf-50... Which means single carb, etc.  Any chance to know if it will indeed hold up to 4 carbs?

[bert96]

 Take a look at ebay UK they have more models...

[MCRider]

This is the one on eBay described as a "Drag Bike Throttle" It is actually for a husky dirt bike. 2 positions and less money than on eBay.
http://www.huskyclub.com/magura.htm

Scroll down to the Magura 314

[A Grove]

I like the magura option..

But my question now iss...

Your throttle has to move a certain distance of cable to make the bike hit "WOT"... how can I be sure I am going to get a throttle that will be able to pull enough cable to hit WOT?

[MCRider]

I like the magura option..

But my question now iss...

Your throttle has to move a certain distance of cable to make the bike hit "WOT"... how can I be sure I am going to get a throttle that will be able to pull enough cable to hit WOT?

In my link, it says total stroke 48mm. So see how much cable pull you need, I doubt if its that much. 48mm= 1 7/8"

[A Grove]

DOH!! Missed that part, now to go measure, thanks!