Hydraulic clutch conversion..

[bearfeet69]

Hi, i have a Suzuki GS750EX 1981 engine fitted to Hard Tail chopper. My problem is that the cable clutch is heavy on the hands and difficult for my girlfriend to work clutch lever (her bike). It has been suggested to fit a hydraulic clutch, but this seems to be unknowen area and not sure it is possible. Has been suggested it might be a case of a master cylinder and some hoses, but others mention a change of clutch casing.??? Would appreciate any suggestions/ideas. Thanks

[silverramsrt]

You could try a Moose racing easy clutch, but I can't guarantee it will fit your application.

BTW, welcome to GSR!

[tkent02]

Or you could put on a new cable.

[SqDancerLynn1]

Take the clutch apart and make sure that it has the stock springs.. Someone may have installed HD springs
Make sure the cable is lubed and in good condition. Cable clutch works better than Hyd

[bwringer]

Agreed. Stock springs will give a very nice light clutch pull, but it's very common to find aftermarket heavy-duty springs.

[Steve]

Yet another vote here to check the springs to make sure they are stock and use an OEM (stock) cable.

For some reason OEM cables tend to work better than aftermarket.

.

[blowerbike]

bad cable routing=harder than hell to pull lever in.
get your GF one of those squeezey things to build up her hand strength

[gert du prez]

had the same issue when I installed a new clutch cable because the angle at the shaft (connection of the end of the clutch cable that is screwed onto the rotating shaft that goes into the 'clutch department')
was not an exact 90 ° but a bit less...

just a small deviation from that exact 90° made 'pulling the clutch' several times harder, a good mathematician can you explain by telling about cosinus and sinus why that is...

[Footy.]

Not sure about the mechanism of operation on the later 750 you have, but i intend doing such a conversion over winter on my 78 GS750E. The reason not so much the reliability of clutch cables, although i have had problems with cables, but because of the design of the operating system.

The clutch lifting mech is on the left of the engine and a long pushrod operates the clutch on the right of the engine. I find the adjustment goes slack when the engine is hot because of expansion, and makes finding nuetral harder, which is a pain in heavy traffic. I think this may be why later engines moved the operating mech to the clutch side.

Hydraulic systems "self adjust" to expansion, plus you lose the friction of badly routed cables etc, and get more power for a lighter action. Plus you dont have to worry about a cable snapping miles from anywhere.

I found this on the net, and i think the parts could be adapted to suit my GS. I have engineering facilities, so some adapting would not be a problem.

http://www.xs11.com/xs11-info/tech-tips/modifications/engine/214-hydraulic-clutch-mod-for-the-xsxj11.html

Footy.

[salty_monk]

The 83 750 has the pushrod you describe & does not have any problems with heat...

The 78 1000 has it on the same side of the clutch.

Disproves your theory but I agree the same side mechanisms seem to make more sense.

[Footy.]

The 83 750 has the pushrod you describe & does not have any problems with heat...

The 78 1000 has it on the same side of the clutch.

Disproves your theory but I agree the same side mechanisms seem to make more sense.

Well i wish it was a theory, but i have to adjust the cold setting to zero, no play at all, even then the hot play in the lever gets to around 10mm, and neutral becomes a pain in English traffic.

You cant deny the physics of heat expansion?

Footy.

[tkent02]

No, can't deny the laws of physics, but the engineers designed these things with the laws of physics in mind. It hasn't been necessary to adjust the clutch at all on any of my prior GSes. Or any other cable clutched bike. That's a lot of bikes. Set it up right once and forgetaboutit. No clutch adjustments required for hot or cold, ever. Maybe after a few months with an old cable, maybe after a beginner slipped the clutch forever, but not for temperature changes. Something isn't right down there.

[Footy.]

No, can't deny the laws of physics, but the engineers designed these things with the laws of physics in mind. It hasn't been necessary to adjust the clutch at all on any of my prior GSes. Or any other cable clutched bike. That's a lot of bikes. Set it up right once and forgetaboutit. No clutch adjustments required for hot or cold, ever. Maybe after a few months with an old cable, maybe after a beginner slipped the clutch forever, but not for temperature changes. Something isn't right down there.

Dont get me wrong here, the loose when hot thing does not by any means make for a big problem, its just me being picky. I have worked in engine reconditioning and vehicle engineering for over 40 years, and i just like to improve my own bikes to the best i can get from them. I think a lot of people who like older vehicles feel the same way.


I thought this point was relevant to the original posters problem, as if his girl struggles to pull the lever right back, a small loss of movement range will make things worse.


My clutch cable and lever are set up the best they can be, the pull is very light and i have no "real" problems. There are no mechanical issues in the clutch or mechanism of lift. But i can tell how hot the engine is by the clutch lever free play, and on occasion this has effected getting into neutral smoothly.

My personal view is the engineers who designed these early "big and wide" engines did not always allow for the laws of physics, so much as the cost. There are quite a few bad cam chain tensioner designs on early Jap UJM's, that got redesigned.

I think it was the same with the clutch. Cable systems are cheap, but there is a lot of alloy from one side of these big engines to the other, and that means thermal expansion. The cable mechs that work on the clutch side will not suffer from this, but they add some more width.

As the big fours evolved and got narrower this extra width mattered. The later GSX air/oil cooled engines ran the same basic clutch pushrod through the engine as my old GS750E, but with a hydraulic actuator.

The link i posted was about converting from cable to hydraulic on Yamahas, so why bother?

I agree that cables are perfectly OK if set up and maintained properly, but as a "picky" person, my "baby" is going to get a hydraulic conversion this winter

Footy.

[salty_monk]

Wow.... knowing how hot it is in England (I'm from there) I'm surprised I can even change gear when running in the Los Angeles traffic at over 100 degrees....

[Footy.]

Wow.... knowing how hot it is in England (I'm from there) I'm surprised I can even change gear when running in the Los Angeles traffic at over 100 degrees....

Or perhaps its just because i'am so "hot"

Seriously, the original poster was asking about hydraulic clutches. There is loads of opinions for and against if you google "motorcycle hydraulic clutch conversion"

Regards

Footy