GSX1100ET Gearchange Problems

[GSX-Trike]

A question that may have been asked before to do with gear selection on a 1980 GSX1100ET.

First a bit of background info:

I have a weak left leg due to polio as a child and if the bike tips to the left I'm a heap in the road. About 10 years ago I thought riding a solo was too risky and sold the bike but as we all know riding a bike is like a drug - you can't get it out of your system!!! I went to a local bike show, saw a trike, the owner took me for a spin on it and I'd found a way to get back on a bike. On Eblag was a 1980 Suzuki GSX1100ET that someone had triked, it was unfinished but looked ok so a deal was done.

Roll on a few years and with money available I had the engine refurbished by a "respected" workshop. It wasn't done very well so had to do it myself - properly.

As a trike it weighs somewhere between 350kg and 400kg so whilst rebuilding the engine logic suggested I should up rate the clutch to cope with getting the extra weight moving. I replaced the OEM clutch with an EBC Complete SRK Clutch Kit that included friction and steel plates and springs now I can't get the gears to change when the engine is running, even moving the gearlever by hand it's a struggle. When the engine is not running the gears change with no problem at all !!!!

Has anyone got any idea what the possible cause might be??? I did find some info that suggested the EBC clutches were shit so could it be the clutch is dragging? If the clutch is the likely cause and I should go back to the OEM plates would the clutch cope with moving the extra weight? Also if I go back to OEM should I replace friction and steel plates or could I get away with just replacing the friction plates - the original plates were knackered?

I'm getting tired of throwing money at this project and really need some advice from you guys who have been living and breathing these dinosaurs for years. Any advice would be much appreciated.

[vizman]

welcome to oss

i’d stick oem clutch plates in it, i’ve never found any of the ebc or others any good.

...I’ve not heard about any trikes struggling with the extra wieght, but you could always fit a lock-up clutch...

 

...and a turbo.

[Gixer1460]

SWMBO has a K GT550 that I built for her (f**kin waste of time as she'll never ride it now!) but that pootles around fine with the std clutch.

Plenty of people are throwing bike engines into Smart cars and Mini's and they work with a std clutch.

[GSX-Trike]

Hi Guys thanks for the info much appreciated.

I like the idea of a turbo, the bike part is not standard anyway. Apparently the last owner before it was triked ran it at Santa Pod but I don't know how well it went. He fitted a big bore kit and the ports have been polished. I've fitted usd front end from a 1990 GSXR1100, Dyna S coils and ignition and a custom stainless exhaust was fitted at same time as the new rear suspension. As I can't operate the gears with my left foot I've made use of the holes in the frame where the rear swingarm used to be so the gearchange pedal is beside the rearbrake pedal - I'm sure the gearchange problem is nothing  to do with swapping the pedal to the right as the gearchange is smooth and easy when the engine is not running.

Not sure how this works but will try to include a pic??

 

[Duckndive]

sounds like clutch is dragging

did you soak the fibres in oil for 24hrs before fitting ?

and yes OEM is the way to go

[ral]

Don’t think it would be long before them back wheels were missing if I ad one of them

[GSX-Trike]

Hi DucknDive I didn't know/think about soaking the fibre plates in oil before fitting them!!!! The advice I was given by vizman and Gixer1460 made sense so I ordered new OEM friction plates from Robinsons Foundry. The plates, and a new gasket, have arrived and I'm planning to fit them Wed. I'll have to put them in oil tomorrow to soak.

Yes ral I quite like the rear wheels too that's why I've fitted locking wheel bolts, use a chain lock through the wheel spokes and rear suspension and got a motion sensor fitted

[Swiss Toni]

Bet you forgot about your 10% OSS discount! 

[GSX-Trike]

Hi Swiss Toni yes I forgot about the 10% discount and the saga continues!!!!

The new friction plates were soaked in oil for 3 days before being fitted. However the clutch still drags???

Whilst I was contemplating how to set fire to the bloody thing so I could claim on the insurance I remembered when I dismantled the engine to refurbish it that the spacers in the middle of the clutch springs had spring washers under them!!!! At the time I thought the "experts" who refurbished the engine had done a bodge job but perhaps they put back the parts a previous owner had fitted - though they should have told me.

When I bought the trike I was told the engine had a 75mm big bore kit fitted by a previous owner and was run at Santa Pod. On stripping the engine I found the inlet and exhaust ports had also been polished. I now wonder if that previous owner who had done these mods also tried to modify the clutch?

To investigate the possibility I stripped the clutch - again - and took some measurements.

The new spacers are 14mm long, the old spacers are 13.2mm long and the spring washer is 1.8mm thick = 15mm or 1mm longer than the OEM spacers.

So if the old "spacers" were 15mm long and worked what, if anything, has been done to the clutch hub to cause the OEM spacers to be "too short"? I also compared the thickness of the old clutch plates with the new ones and the dimensions are the same which rules out a problem with varying thicknesses there.

Next I did some measurements on the clutch hub and this is where I'm hoping you guys can help. The dimension from the front face to the top of the spring post on my clutch hub is 12.8mm and the dimension from the front face to the 1st plain (steel) plate that is held in by the wire retaining clip is 47.6mm. Does anyone have a clutch hub available they could measure and tell me if these dimensions are correct please? And if they are not correct what they should be?

If these dimensions are not correct I will get new spacers made to compensate for the difference. If these dimensions are correct then the mystery deepens?? I will then get some spacers made 15mm long and try them.

Thanks for any advice you are able to offer. Somewhere amongst this diatribe should be a picture with the dimensions I took marked on it as well as a picture showing the "spacers" I replaced.

[Hacri]

I can check tomorrow.

[GSX-Trike]

Thanks Hacri. It will be interesting to know if the clutch hub has been modified and if it has why? And if it hasn't why the "spacers" that were fitted are 1mm longer than OEM? Tho I don't suppose I will ever find out.

[Swiss Toni]

The differences in the clutch basket posts & spacers, was a factory mod to the later models. There was also a change to the big centre spacer (shorter, I think?), and there was a new thrust washer fitted. I also seem to remember, the shaped (sort of like a 'Bellvile') washer, at the bottom of the plate stack, was changed, and reversed! 

Edited March 21, 2019 by Swiss Toni

[arnout]

I measured similar numbers on my ET hub. But also with regards to the spacers this only matters for the preload on the springs and should not affect the plates freeing up with the lever fully pulled. Unless.. the spring coils are binding or the clutch lever or cable in some way prevent full travel of the pressure plate. So that is what I would check if you haven't already.  Maybe pushing on the arm on the clutch cover wil reveal unused travel? If so maybe a non-stock clutch lever was installed with a different ratio and less travel?

[GSX-Trike]

More background info:

I had polio as a child which left me with a weak left leg and I need to wear a caliper and raised shoe. All the Japanese bikes I've ridden in the past, including a GS550, I have managed to operate the gear lever ok but for some reason (getting old and knackered perhaps?) I can't get my foot under the gear pedal to lift it on the GSX1100ET. I fitted a Kliktronic Push Button Gearchanger but it was hit-or-miss with finding neutral. The suggestion was to select neutral whilst still moving which isn't easy in stop-start traffic!!! Because it's a trike there were 2 redundant holes in the frame where the rear swing arm used to be. I had 2 brass bushes made, had a gearshaft modified, modified a gearchange pedal and fitted various linkages and now got a right foot gearchange. With the engine stopped and rocking the trike back-and-forth it goes through all the gears really easily.

 

So back to the plot.

1. The clutch lever I am using is not the original but worked before I put the OEM spacers in the clutch. The clutch release arm on the clutch housing has 12mm movement from no slack in the clutch cable to when the clutch lever is fully pulled in.

2. The clutch basket rocks side-to-side about 0.3mm - it feels more than that so I'm going to get a new bearing.

3. The end float on the clutch basket is about 0.3mm. Should I reduce the end float? As best I can make out from the Haynes manual the modified spacers were fitted in later years to my engine?

4. The side-to-side movement on the clutch release rack is 0.3mm and the pinion has 0.2mm. As the 2 combined is 0.5mm could this have an effect on the operation of the clutch? Though as in Item 1 the clutch release arm has plenty of movement in it!!!

5. Where the clutch release rack fits into the hole in on the inside of the clutch there seems to be negligible wear.

6. There is slight ridging on the centre hub and inside the basket. Would it/could it cause a problem if I carefully removed some of the high spots with a very fine wet-and-dry paper?

 

Are there any other checks/measurements I should do?

[arnout]

Right.. If you have found the travel of the clutch isn't hampered by the different lever or other mods, then there most be another reason for the clutch dragging.

Quote

6. There is slight ridging on the centre hub and inside the basket. Would it/could it cause a problem if I carefully removed some of the high spots with a very fine wet-and-dry paper? 

Not exactly sure what you mean here. But the tangs on the clutch plates do leave indentations where they've been rubbing in the grooves of the hub and basket. If these become severe there is an enlarged possibility the plates might not free up as easily upon pulling the lever as the tangs get stuck in these notches.

So another thing to check: are the indentations particularly severe?  Mild indentations on the sides of the grooves are quite normal though.

Removing or flattening these bumps is tricky though. A way to check if this actually is the culprit (or a quick fix if it is) is by moving the position of the tangs by  altering the clutch plates stack (by adding/removing a plain plate) so that the tang wil sit on top of the bumps rather than in the indentations.

Quote

3. The end float on the clutch basket is about 0.3mm. Should I reduce the end float? As best I can make out from the Haynes manual the modified spacers were fitted in later years to my engine?

Yup the later engines like the one in the EFE, had a slightly narrower center spacer that allowed for adjustment shims of different thickness to be added to solve the well known GSX clutch rattle. This end float rattle isn't a particularly serious problem though. It does the engine no harm apart from the fact the constant hammering is probably the reason why so many center nuts do loosen over time. (But this is kept from undoing itself fully by the lock washer).

As for finding neutral at standstill, I suspect the gearchanger system you are using might not allow for the more subtle touch that is needed to select it. There is a knack to it, but once mastered you'll never have trouble engaging neutral again. At standstill slightly let the clutch out so the transmisson is put under load but not enough to actually push the bike forward. Now gently push the gear lever up from first gear position and the gearbox will easily shift into neutral.

[Blower1]

I have two EFE. Both had slight problems to find neutral at standstill (stiffer clutch springs). Then I took clutch steel plates to machine shop for

level grinding. The machinist told that there were about 0.05mm high spots even the new steel discs.

After level grinding both clutches has been working perfectly.

[Gixer1460]

I understand the conversion for your disability but some of the relative lever angles could be improved and there are a lot of joints that introduce slack / backlash so 'delicacy' in gear selection could be problematical. My first thought when you described your problem was use an old C90 type 'heel and toe' type shifter - very direct and don't have to move your foot at all - just rock it, toe down  or heel down for gear selection?

But the GSX clutch is a 'bit agricultural' as regard tolerances and will appear sloppy / loose / worn when its fine with no problems. The hubs and baskets do suffer with the 'ridging' noted above, both being aluminium doesn't help together with steel of the plates. They can be filed out to smooth off but its a temporary fix - the symptoms will usually return, replacement is ultimately the required fix! Flat steels essential - grinding fairly extreme for a road bike - just make sure none are warped. Assume you are using OEM Suzuki fibres - others can be problematical, proven many times via this site and racing community.

[GSX-Trike]

Gentlemen thank you all for your input and advice.

The wear on the centre hub and clutch basket caused by the clutch plates is minimal so I will leave it for now - trying to remove an equal amount from each groove could also be very difficult without precision machinery!!!

As I've got the clutch partly dismantled I will replace the clutch basket bearing - I just have to work out how to get the 10% discount from Robinsons Foundry?

It seems all the dimensions regarding the clutch basket and clutch lever/operating arm movement are correct so why the clutch won't clear with the correct spacers in is a mystery?? There's no telling what any previous owners have done!!! To get the trike back on the road I will get a set of 15mm spacers made and see how it goes. If the clutch starts to slip once everything has bedded in I can fit the OEM spacers.

The gearchange linkage was made and fitted after the refurbed engine was fitted and hasn't been road tested yet as the clutch has been a problem. However, with the engine not running the gearchange is really easy to move and nice and smooth. There is plenty of adjustment in the linkage which will allow me to alter pedal position and operating arm angles which I can fine tune once the trike is back on the road. Initially I will paint the bare steel parts with Hammerite then over next winter I will get the parts powder coated and at the same time replace the ball joints in the linkage. That's if the mechanism works and my brain can get used to a right foot gearchange!!!!!

Once again gentlemen thank you all for your input and advice and I'll try to keep you updated on how it all goes.

It's beautiful sunny weather here in Colchester so my trike should be out on the road and not stuck in the garage. Enjoy your bikes gents and safe riding.

[Cheeky4648]

What engine oil are you running ?

[Hacri]

I'm sorry i didnt come back with the measurements i promised, but my back is acting up, so not been able to check

[GSX-Trike]

The oil I am using is Rock Oil WRX 2 10W40 kindly donated by the "experts" who "refurbished" the engine.

I've got the new parts I ordered and 15mm spacers have been made so at the weekend I will put the clutch back together and see what happens?

[Ibbo]

I don't think it's you're problem, but I've had a few engines converted to right hand change.

The best way is to extend the gearchange out through the clutch cover. The linkages never work as well as the direct approach.

Mike

[Swiss Toni]

On 24 March 2019 at 1:03 PM, GSX-Trike said:

 

As I've got the clutch partly dismantled I will replace the clutch basket bearing - I just have to work out how to get the 10% discount from Robinsons Foundry?

If you order your spares via the website, there'll be a voucher/discount box near your basket. Enter 'OSS Discount' or by phone, just tell Michelle or Michael your OSS username. Simples!  

[GSX-Trike]

I've finally got the clutch sorted.

I took the clutch to Suzuki Performance Spares for Nick to have a look. Straight away he said the pressure plate was wrong, it was off a GS1000? Everything else was well within limits so I bought a 2nd hand GSX1100 pressure plate from him, went home, swapped the clutch release rack from the GS1000 to the GSX1100 pressure plate, fitted the clutch, filled the engine with oil and tried it.

The clutch still dragged!!!!!

After considering how to set light to the bloody thing so I could claim the insurance I decided to take all of the adjustment - and some - out of the clutch cable and tried again.

It worked.

After going online and using factory parts lists to compare the GSX1100 and GS1000 clutch parts I decided to buy a Clutch Release Rack for the GSX1100.

I had wondered if the pitch of the rack teeth were different or something similar but the 2 racks were identical in that respect. The difference was in the position of the groove for the 'C' clip - the GSX1100 groove is 0.5mm closer to the underside of the 'mushroom head', not a lot but made all the difference!!!!!

The clutch, now hydraulically operated, and the right foot gearchange work perfectly tho, as has been said, I have to select neutral whilst still moving.

My trike is now MOT'ed and taxed and hopefully in the not too distant future I'll get used to changing down a gear without operating the rear brake lol????

Thank you gentlemen for your help and advice and hopefully this info might help someone else with a similar clutch problem.

[R1guy]

On 3/23/2019 at 10:17 AM, Gixer1460 said:

I understand the conversion for your disability but some of the relative lever angles could be improved and there are a lot of joints that introduce slack / backlash so 'delicacy' in gear selection could be problematical. My first thought when you described your problem was use an old C90 type 'heel and toe' type shifter - very direct and don't have to move your foot at all - just rock it, toe down  or heel down for gear selection?

 

- good thinking