Power assisted motorcycle clutch cable. Ideas?

[Morrisman]

As I’ve mentioned on one of the bike threads, my left hand is getting gradually more feeble, and having trouble pulling the already light clutch in on my BMW 310 bike. I’ve been wondering if there is some sort of electric actuator gadget that could be used to either pull a cable, or act directly onto the lower clutch arm. And do it exactly as the hand clutch lever is operated.

I’ve seen something similar advertised in the US, for Harley’s, but there is zero information about how it works, or what components are used. Ands it’s $700

I’ve noticed more bikes are being built nowadays with automatic transmissions, Hondas E-clutch looks very impressive but also hellish complicated.

I could be looking at a scooter eventually though, as it would need to be fairly light.

The original Boss Hoss V8 motorcycles came with a vacuum assisted clutch, using a brake booster. Probably quite big and chunky though. They were basically direct drive, no gearbox.

 

[Pete.]

Make a longer arm or extend the one you have. That will reduce the force required at the lever. You might have to keep it carefully adjusted.

 

[barracuda816]

Could be a fun project with an esp32 and a servo motor? That's how I would approach it, you can get some high quality powerful small servo motors in the RC car would for not ridiculous amounts of money.

 

[Agroshield]

Would a hydraulic clutch work?

https://magura.com/en/EUR/technology_innovation/motorcycle/hymec

 

[bricol]

Trying not to be a killjoy, and having not ridden a motorbike, I have no idea of the use of the clutch lever on on - but if you can't pull the lever easily, should you be riding the thing in the first place if grip is poor?

 

[Morrisman]

Make a longer arm or extend the one you have. That will reduce the force required at the lever. You might have to keep it carefully adjusted.

The problem then is the clutch doesn’t pull as far, and I find it hard to get neutral unless the lever is pulled right back to the bar. On most bikes that system wouldn’t be a problem as they only use a short area of the lever travel.

Could be a fun project with an esp32 and a servo motor? That's how I would approach it, you can get some high quality powerful small servo motors in the RC car would for not ridiculous amounts of money.

That’s the sort of thing, if I could find the right servo. Trouble will probably be me trying to construct a mechanism to get it all working, but I have a friend who is very handy and has some precision engineering tools.

Would a hydraulic clutch work?

https://magura.com/en/EUR/technology_innovation/motorcycle/hymec

I did look into it, but I doubt it would be a much easier pull than the new cable I’ve just fitted, unless the ratio was reduced, but that brings up the issue of clutch travel again.

Trying not to be a killjoy, and having not ridden a motorbike, I have no idea of the use of the clutch lever on on - but if you can't pull the lever easily, should you be riding the thing in the first place if grip is poor?

You’re not wrong, at the moment the worst thing that can happen is stalling the bike in slow traffic, but there are people out there riding bikes with just one arm, so its not impossible.

 

[8ob]

It may be possible to rig up a leccy handbrake motor, frig that through a potentiometer on the hand control lever.

Bob

 

[Erie Fred]

I'm thinking of how drum brakes "cam in" to add power assist (sort of).
Might be a design there.

A centrifugal clutch is out ?

 

[oldbikedavey]

Solenoid assisted hydraulic system ?
Or even a solenoid assisted mechanical lifter arrangement like the three-ball BSA/Triumph setup ?

 

[waddycall]

Can you get into the clutch itself? It doesn’t really sound like it’s right.

 

[Agroshield]

...there are people out there riding bikes with just one arm, so it's not impossible.

Is it worth looking about in this area (people with disabilities or reduced movement) to see what the possiblities are for each of the bike's functions? That could give you some ideas for your own situation (e.g. https://www.kliktronic.co.uk/the-k-lever2-clutch-brake-system/ which gives you a right hand clutch lever). See also: https://www.nabd.org.uk/armdisabilities/ and https://disabledmotorcycleriders.com/

There is something called a Rekluse RadiusX autoclutch that comes up in a search with BMW 310. It looks like a centrifugal clutch as suggested above, but also looks only to be available in the US.

 

[premmington]

Trade out the BMW 310.

In with a scooter...

@Morrisman - I took a SH350i out the other week - did some electrical work on it for a trader.

I was supprised how nice it was to ride - but rear brake is on the handlebar - clutch side.... (most scooters are configured like this).

Unless you wanna go for a C90 type thing.

 

[Ubique]

Firstly, I know little about motorcycles....
If there is a way of creating & storing vacuum, would it be possible to create some sort of vacuum assistance system, in a similar way to car brake booster?
I'd also advise that you check construction & use / IVA implications, and by association, insurance.

 

[Hood]

I have the Africa Twin DCT and absolutely love it, DCT is only available on the Africa Twin, Goldwing, X-ADV 750 and NC750.

E-clutch is simpler, basically just like having a quick shifter but with the ability for the clutch to be automatic when stopping/starting if wanted.

Yamaha has the Y-AMT on the MT09 now I think. It is sort of a halfway house between DCT and E-Clutch in that it will also change gears but clutch and gears done via a solenoid.

BMW have their ASA now but just on the R1300GS I think.

KTM were coming out with an auto version but when that will happen with their woes is any ones guess.

The CFMOTO 450MT seemingly has an extremely light clutch so may suit but think they are almost impossible to get hold of as the demand for them has been so high worldwide.

 

[Hood]

Loos like Rekluse do a kit for the G310 GS.

https://www.rekluse.com/product/auto-clutches/radiusx/radiusx-clutches/radiusx-bmw-g310-gs-r/?srsltid=AfmBOoquGKcId3oWSSO73cHYKzzDJuOn6s68hrxJkSezAbYOvTVsH2w4

 

[nickk]

Aswell as extending lever length,you can also change the attachment hole for the cable nipple,may have to fill the old hole if there’s inadequate meat around it for a new hole,that’ll give you a leverage advantage.

 

[Nomad]

Ask NABD, they have experience modifying bikes for riders with very serious disabilities (missing limbs etc) so I'm sure they will have options for a weak grip on a lever.
Hope you find a solution, keep us updated.

National Association for Bikers with a Disability (NABD)

UK The NABD was set up in April 1991 by six bikers from Stockport and Manchester who would not accept the idea that disabled people could not ride motorcycles, scooters, sidecar outfits…

arn1e.co.uk

 

[Keithmac]

Rekluse clutches are very good for off road bikes, I don't believe they offer any advantage for lever operation though, but you don't need to pull the leaver when stooping or setting off, just changing gear.

As you know you cannot alter the pivot points to allow easier engagement as you will loose the required distance to fully release the clutch.

Softer clutch springs maybe worth a try if you are not a flat out everywhere rider but you would sacrifice some clamping force.

I have ridden a few DTC Hondas and they are very good, but the bikes are significantly bigger than your 310.

Hydraulic wise you are in the same boat as the cable, for correct clutch basket cover movement with the original springs the master to slave cylinder ratio would make the clutch the same effort to apply.

Rotax engined Apilia RSV 1000's had a vacuum diaphragm built in to the clutch cover, clever really as at high vacuum (low throttle) that would assist clutch disengagement but at high throttle (no vacuum) it would allow full camping force.

 

[Keithmac]

Auto correct has wrecked the above post..

 

[Hood]

Rekluse clutches are very good for off road bikes, I don't believe they offer any advantage for lever operation though, but you don't need to pull the leaver when stooping or setting off, just changing gear.
...

A Healtech quick shifter could be used in conjunction with the Rekluse thus basically making the clutch redundant. How well the Healtech works I have no idea and also not sure if it downshifts as well as upshifts but I think it will.