good old fashioned british know how

[captaindonutbikes]

so got my CR29s fitted all sweet and just dialing them in.

due to the throttle cable length difference from the standard carbs i have switched the return cable to act as the pull on the throttle.

i makes for less turn on the actual throttle but the carbs reach their lock positions.

does anyone foresee any problems with this ? have had it running and it seems o.k, but should the throttle have more travel available for the carbs ?

[SteveD CB500K0]

Sounds like a quick-action throttle then!

We spent money back in the 70's on special quick-action throttles that basically replaced the handgrip with one of a larger diameter - it was the only way around the "two handfuls of throttle" issue.

Steve

[captaindonutbikes]

she is quick for sure !

just checking its not going to cause 'over fueling' by the carbs but seems my moment of genius (they are very far and few between ) has worked.

[K2-K6]

As long as they close safely then it shouldn't cause a problem. Although it's difficult to judge it without looking at it.

The action is probably an intended difference in the carb design to give a quicker throttle action for their type of use (ie race orientated) with a standard type twistgrip, the cable can't change this.

This is a bit obscure but the original Honda pull cables had a nylon/ plastic internal sleeve inside that tight turn coming out of the twistgrip, not sure if the closing cable is also equipped. The effect without it is that you can have difficulty particularly when you start to open the thottle and the tension feels high friction so you struggle for any subtle control as you start to roll it on.

[florence]

If the throttle is opened too quickly on these bikes it stalls a little.  I am sure with carefull use you will be fine.  I like the idea, the throttle action on these bikes is a bit tiresome.

[K2-K6]

Just a further thought, many of the Honda twin cable arrangements have a fixed non adjustable cable to act as the safety return pull with the opening cable being adjustable for length.

This is so that you can set enough slack into the operating cable to allow the bars to go from lock to lock without pulling the throttle open and changing the speed of the bike unintentionally so I would say you have to be able to set it up like this to make it ok.

If you think it through further, if the bike were involved in an accident and subsequently inspected by a motor vehicle engineer do you think it would stand up to that level of scrutiny because your insurer would expect it to.

[captaindonutbikes]

good point.

the return spring on the carbs snap shut when the throttle is released. i know that some race setups only use pull only so may be worth looking into.

[K2-K6]

Sounds like it's coming along though, some pics would be interesting to see.

I've even ridden many things with "get you home" interpretations in the past but everyone gets so serious about stuff like that now so if anything is percieved as wrong somebody somewhere starts demanding answers.

I think the original reason for two cables was that they normally had one return spring so in the event of failure you could manually close the throttle. If you have more / backup springs, then I'd guess you've no need to have a second cable.

[captaindonutbikes]

There is more than enough slack in the cable for lock to lock.

if it passes an MOT then surely it would withstand engineering scrutiny in the event of an accident?