Bike carbs, throttle pedal

Please restrict your questions and replies to Capri related technical issues!
Post Reply
-JC-
Posts: 4412
Joined: Mon Jul 28, 2008 1:17 pm
Car(s): 1986 Ford Capri 2.0 Laser
2004 Mazda RX8
Location: Surrey
Contact:

Bike carbs, throttle pedal

Post by -JC- »

I installed my bike carbs earlier in the year (40mm Keihin CVKs). Did the usual bicycle brake cable for use as the throttle cable. Seems mostly ok so far, but the pedal is sitting a lot lower, and as such there's less travel. Can't get my head around what I need to change or adjust to sort it, if that's even possible.
Image
"Hard work often pays off after time, but laziness always pays off now."
Mc Tool
Donator
Donator
Posts: 2358
Joined: Sat May 17, 2014 8:34 pm
Car(s): 1980 mk3 capri 2l ohc T9 , Toyota Blade Master 3.5l V6, Paso , 850T,rd400, 900ss
Location: Invercargill New Zealand

Re: Bike carbs, throttle prdal

Post by Mc Tool »

The easiest way to gain more travel is to move the cable attachment point on the accelerator pedal closer to its pivot point, and not by a whole lot. This will increase the amount of pedal travel required to get the same cable travel........all to do with lever ratios
Sometimes I talk to myself ... and we both have a good laugh
-JC-
Posts: 4412
Joined: Mon Jul 28, 2008 1:17 pm
Car(s): 1986 Ford Capri 2.0 Laser
2004 Mazda RX8
Location: Surrey
Contact:

Re: Bike carbs, throttle pedal

Post by -JC- »

Thanks. Is there adjustment down at the pedal for that then? I hated fiddling about with that stupid clip thing, so awkward to get at!
Image
"Hard work often pays off after time, but laziness always pays off now."
User avatar
stevemarl
Donator
Donator
Posts: 4906
Joined: Wed Jul 11, 2012 6:31 pm
Car(s): Capri 1.6 laser

Re: Bike carbs, throttle pedal

Post by stevemarl »

Would it be easier to change the arc at the carb. end, moving the attachment point further away from the pivot to increase travel, a little extension lever perhaps (the opposite of what you`d do at the pedal)? . Maybe easier to work on there too?
Mc Tool
Donator
Donator
Posts: 2358
Joined: Sat May 17, 2014 8:34 pm
Car(s): 1980 mk3 capri 2l ohc T9 , Toyota Blade Master 3.5l V6, Paso , 850T,rd400, 900ss
Location: Invercargill New Zealand

Re: Bike carbs, throttle pedal

Post by Mc Tool »

Yeah ,I did think of that but them carbs come as a well sorted (both in function and adjustability ) assembly and figured best left alone, so at the other end what you have to do is move that ball thing that the proxy (and it is ) clip thing goes on closer to the pivot and that is going to involve a bit of light engineering.
The other option is to just give it a whirl as it is ,allow yourself a bit of time to get used to it proper, maybe "manipulate" the accelerator pedal a bit to get it in the right spot
Sometimes I talk to myself ... and we both have a good laugh
-JC-
Posts: 4412
Joined: Mon Jul 28, 2008 1:17 pm
Car(s): 1986 Ford Capri 2.0 Laser
2004 Mazda RX8
Location: Surrey
Contact:

Re: Bike carbs, throttle pedal

Post by -JC- »

Cool, thanks, will have a look. I think I have a spare pedal somewhere, so I can maybe look at it out of the car at least.

I don't think it'd be easy to alter it at the carb. It's not a lever, it's like a spindle kind of thing, and there wouldn't be enough room for anything bigger.
Image
"Hard work often pays off after time, but laziness always pays off now."
Not_Anumber
Donator
Donator
Posts: 894
Joined: Sun Jan 15, 2017 3:54 pm
Car(s): Just sold 1983 2.8 Injection 5 speed. Currently restoring another classic Previously owned 2 Capris. Likely to own another at some point

Re: Bike carbs, throttle pedal

Post by Not_Anumber »

Rather than modify the pedal or risk upsetting the linkage on the bike carbs you may find it easier and neater to take the cable from the pedal to an adjustable pivoting linkage and then a short cable from there to the carbs.

This one might not be suitable but shows the concept:

https://www.ebay.co.uk/itm/SYTEC-TLK1- ... SwDlNc5B~Q

It may be worth a call to Bogg brothers who do lots of bike carb conversion parts to see what they use to do the job as the need for reduction gearing for accelerator cables must come up quite often.
User avatar
nigecapri
Posts: 5795
Joined: Mon Jul 28, 2008 6:31 am
Car(s): Black 2.0S with supercharged bike carbs.
Location: http://www.blacklabradorpuppies.co.uk/
Contact:

Re: Bike carbs, throttle pedal

Post by nigecapri »

Can you post up a photo of the carb spindle where the cable fixes.
Boggs did mine (many moons back) & it got me to the next town before giving up. I fabbed a makeshift repair then made up a new system at home. Improved return spring from a Bedford CF van carb straightened & rewound in the retainer then a new cable & adjuster in the clasp. The pedal is as per original positions.
User avatar
Toecutter
Posts: 163
Joined: Wed Jun 26, 2013 10:07 am
Car(s): 1973 Mk1 (Facelift) Capri - 2.0 Pinto on Bike carbs
Location: Éire

Re: Bike carbs, throttle pedal

Post by Toecutter »

I have 40mm cvk carbs fitted to mine from my zx9r, by pure chance I thought I'd try the throttle cable from the bike as well and it was a perfect fit and length.
I ran it over the rocker cover and through the existing hole in the bulkhead, the only mod needed was to ground the nipple :shock: down at the peddle end so the clip would fit over as standard, it works perfect. If your carbs are the same type then picking up the bike cable could be a good option for you too. It was a bit handier for me cos I had all the bits anyway.
Image
-JC-
Posts: 4412
Joined: Mon Jul 28, 2008 1:17 pm
Car(s): 1986 Ford Capri 2.0 Laser
2004 Mazda RX8
Location: Surrey
Contact:

Re: Bike carbs, throttle pedal

Post by -JC- »

nigecapri wrote: Tue Jul 23, 2019 7:17 pm Can you post up a photo of the carb spindle where the cable fixes.
Boggs did mine (many moons back) & it got me to the next town before giving up. I fabbed a makeshift repair then made up a new system at home. Improved return spring from a Bedford CF van carb straightened & rewound in the retainer then a new cable & adjuster in the clasp. The pedal is as per original positions.
Kinda hard to get a good angle, but a few photos : https://imgur.com/a/lYtYzZX
Image
"Hard work often pays off after time, but laziness always pays off now."
User avatar
nigecapri
Posts: 5795
Joined: Mon Jul 28, 2008 6:31 am
Car(s): Black 2.0S with supercharged bike carbs.
Location: http://www.blacklabradorpuppies.co.uk/
Contact:

Re: Bike carbs, throttle pedal

Post by nigecapri »

Just blank black boxes showing - maybe not available unless a member & logged-in???
User avatar
Andrew 2.8i
Donator
Donator
Posts: 14723
Joined: Sat Jan 25, 2014 7:38 pm
Car(s): '83 2.8 Injection (sunny days only)
'04 Toyota MR2 (owned from new)
Location: Ceredigion
Contact:

Re: Bike carbs, throttle pedal

Post by Andrew 2.8i »

nigecapri wrote: Thu Aug 08, 2019 9:28 pm Just blank black boxes showing - maybe not available unless a member & logged-in???
I'm not a member of Imgur, the photos are showing fine for me. Maybe a browser issue at your end?

I hope JC doesn't mind, but I've posted his photos directly onto the forum.

Image
Image
Image
Image
Image
Image

Andrew.
Image
User avatar
nigecapri
Posts: 5795
Joined: Mon Jul 28, 2008 6:31 am
Car(s): Black 2.0S with supercharged bike carbs.
Location: http://www.blacklabradorpuppies.co.uk/
Contact:

Re: Bike carbs, throttle pedal

Post by nigecapri »

That looks similar to mine although the Mikunis on mine have the throttle cable mechanism at the front end of the spindle.
Maybe take your cable to a motorbike / cycle shop and see if they have anything similar but with a shorter inner cable / same length outer cable which should lift your pedal a bit?
-JC-
Posts: 4412
Joined: Mon Jul 28, 2008 1:17 pm
Car(s): 1986 Ford Capri 2.0 Laser
2004 Mazda RX8
Location: Surrey
Contact:

Re: Bike carbs, throttle pedal

Post by -JC- »

Thanks, that might be worth a try!
Image
"Hard work often pays off after time, but laziness always pays off now."
Post Reply