I have a 1980 GSX1200(was 1100) but it still has the standard clutch with heavy duty springs. I allways use the recommended oil(10/40) and insure its level is within the marks etc.   I bought the bike like it is now a few years ago and have been riding her as often as I kan,all the while with my slippy clutch! The only things i did change where the clutch plates,thrust bearing and heavy duty springs,all new. I did this just incase it was as simple as that,but no!   As is maybe obvious to you who do know,I dont know that much about such things..it will be obvious soon if u got the patience to continue reading! I just got my common sense really!    Now its obvious to me that an 1100 clutch is designed for an 1100 engine! I have had various things suggested to me such as...   1) Pre-load the heavy duty springs with spacers? IF SO HOW BIG SHOULD THESE BE and WHERE ON THE SPRING SHOULD IT GO..INSIDE(nearest clutch plates) or OUTSIDE(Nearest to casing)?   2) Buy some heavier duty clutch springs..RACING SPRINGS and maybe space these out?   3) Use a different oil. I bin told u kan run these 80s air cooled engines on just bowt any oil??   Any more suggestions are most welcome and will be gratefully recieved. PLEASE PLEASE HELP!! Under acceleration the clutch slips just as my power band is starting to get fun. The bike i had before this for many years was a 79 GS1000 with a quarter throttle. I could give this a full handfull and no slip ever,where am i going wrong with my GSX??                                                                                                                                                                                   

may be daft question but are you using 10/40 car oil or motorbike oil?
                                                                                                                                                                             

     these bikes will run on any oil, 10/40  20/50 etc.  use a mineral oil as this is what they were designed to run on.
        if you are preloading the springs, and i am assuming you have a number of bolts tightening up against the springs here, put the spacers under the head of the bolt so it squashes the spring up more. use washers and add one to each bolt at a time and see if there is a difference. but bear in mind if you go too mad you will strip the aluminium threads and junk your clutch basket.
  before you do any of this have you replaced the clutch cable? 1980 seems too early for a hydraulic clutch, and is it properly adjusted, or is it biting too late?
    i wouldn't have thought an extra 100cc would make that much difference so has it been ported, high lift cams etc?
       how many miles has it done? it is possible the clutch asket is notched and this is holding the plates apart.
   just the random ramblings of a madman but might help. good luck.

To exup 35.   Fanxs for reply doowd.   I was using 20/50 cheapo crap from Tesco. I started buying 10/40 cheapo crap from morrisons,it does say that it is for bikes!?    I started using this after my m8 reabuilt my top end after replacing the gaskets.                                                                                                                                                                             

I used to have a GSX600F that was tuned and the clutch slipped at high revs, so had the whole thing replaced. But as for the 1100 clutch being designed for the 1100 engine I'm not so sure. Remember the problems with the clutch the old FZR1000ExUP used to have? seems it was because the same clutch that was used in the 400RR was used in the bigger bikes too. (I think they got around to sorting it by the time the YZF came out)   As for oil - I would go with a decent brand such as Shell, Mobil, etc and make sure its a motorcycle oil - as you'll know anyway bikes usually have a wet clutch, whereas cars usually have a dry clutch - so the oil isn't designed with clutches in mind.   as XJ says - basket could be notchy/grooved                                                                                                                                                                             

In reply to xj   Hey fansalotinnit for reply. You covered a fair bit so here goes. I will start by saying,I am very mechanically/practicaly minded BUT i know nothing of mecahanics to speak of! I learn pretty kwick!   The oil i am using now is mineral oil. My clutch is not hydraulic and i havent ever replaced the clutch cable. I presume the cable could maybe have stretched which may make a bit of difference.? As for adjustment,I am experimenting with that!    Like i say i got no experience with such fings,just common sense. What may seem very "elephant-tree" (elementary!)to many is only elementary if you'v dealt with it before. Best to pressume i know nothing as wot i may know maybe wrong?!    I presume that adjustment at top end,on me bars, just decides when the clutch is opened n closed? So u must meen adjustment at bottom,on the turney shaft wot the cable attaches to.?    I have been experimenting with bottom end adjustment. I operated the clutch lever in n out to understand the action. The cable turns the rod by pulling a lever attached to said rod. The cable adjuster thing(screwed into bracket on gearbox)seems to be the adjustment i think you are on about?   If i screw this out a bit towards the lever will this do it OR do i move the lever around on the rod? I honestly dont know much other than wot i have worked out myself! It says in the hand book that adjusting the bottom adjuster does the freeplay on the clutchlever at the top?! On which bit do i have to adjust to alter the bite?    My m8 checked clutch basket when he did gaskets. At the time he pointed at various bits and said thats good,that should be ok and i shouldnt have any problems! As to weather or not its notched i couldnt begin to say,I wouldnt know where to look for notches?! If it is notched is it something you can hear when engine running at a standstill? I have heard people in the past comment about their own bikes saying "they have a bit of clutch basket rattle" but havent ever experienced dis myself. The bike is not standard and has had a few owners. There is a mileage on the clocks but I cant see it been corresponding to that engine as i dont know wot they did to it before i got it. I know that it was used on the dragstrip at the bulldog as i got two tickets with the logbook! I have changed the clocks for more suitable ones as i didnt like the massive rectangular block on mi bars..twas huge.    I dont know about high lift cams but i think its been ported. How can i tell if its got high lift cams or not. I bought the bike about five years ago from a lad that had moved to lincoln from Brighton. I havent seen him for about four years,I think he moved back so i kant ask him,thats presuming he knew?    I have bin ridin mi bike for 5yrs with slippy clutch syndrome. When i first got her i put new plates n springs in myself. I am no good at understanding handbooks,I prefer to be shown or work it out. The clutch plates i took out(which i kept)did not look hardly worn at all when i compaired them. The springs i took out had shortened compared to the new heavy duty ones i put in but looked the same type. I replaced the thrust bearing as it was cheep n bloke in shop suggested i did.! I have adjusted various bits in and owt etc(on the cable) but just seemed to make it worse so i put it all back as it was! I wish i knew how to set it up properly myself in the 1st place as then i could tell if it wasnt working properly.    I have offered a few people over the years, to go ride my bike n see wot they think. HOWEVER..an early 80's beast is a complete different kettle ov water born wiggley things to a plastic crotch rocket or a harley lookalike! As a result all offers were turned down due to the nature of the beast!   I dont know enough to make wot i explain,enough to allow people to understand the problem so there for i feel rather disconbobulated bowt it all. I wish i just had the money to give it to my m8 who knows these things n say fix it please I wanna play.I miss my GS1000.   Just the longer ramblings of a former madman,but now much better...self diagnosed of course!! Fanxs for your help doowd,still relatively baffled however..I fink the mists have cleared a little!?                                                                                                                                                                             

I have only had 3 different roadbikes since 95(when i first rode on the road) so my experience is limited. I know wot i know bowt bike mechanics n running from my experiences n problems i encountered allong the way! My 1st was a GPZ600r hardtail wich i did 32 full weekend rallys on in the second year i had it,no probs other than chain n sprocket. My 2nd was a 79 GS1000 which was just fun fun fun with a few small problems over all the years i had it. I got my GSX as i thought it would be more fun than the GS but cant tell till i kan ride her properly without clutch slipping!
  Fanxs for all your help peeps                                                                                                                                                                             

If you've fitted heavy duty springs, which normally give about 10% extra pressure I'd not start shimming it up for more just yet. Those threads can let go if abused.

Go back to basics, check you have enough free play in the cable to allow the clutch to fully engage, also check the cable is free to move and not snagging on the sleeve.

Not sure what make of plates you've got fitted but I've seen some cheap plates that are considerable thinner than the OEM. If possible take one of the plates out and compare it to a genuine part.  

FYI Basket rattle is caused by weak springs an general wear so you shouldn't hear it on yours. Cheap oil is normally OK but synthetic would probably not go well in an old beast like this. I've know oil to cause clutch drag and I've known different oils to cause slip.  Sadly it starts to get expensive if you suspect the oil as the plates get saturated within 24 hours so you have to sling them and replace with new if it is an oil problem.

Basically this is a spend a weekend playing about with different setups problem. So good luck

did you pre soak the new plates in oil ??????? did you put them all in the same way ???? you do find on the outer & inner edge of the fibre & steel plate there is a sharp edge & a rounded off side ... .. rounded side to the engine so will slide over any ridges in the basket & not hold the plates off ..... are your steels all flat & not blued or burnt ...that should keep you going for a bit

Yonks ago I had a cb750 and had clutch slip, I replaced the springs with heavy duty ones from work and kept adding pressure till clutch centre collapsed, in the end it was just a wanked sticky cable not going back that last bit. Put everything back the way it was and change the cable, or at least release cable at both ends and see if it runs freely.

if you've had it 5 years and not replaced the cable it's the first place i would look. either a new one or get a cable oiler and make sure it is free and easy. would be tempted to go for a new one if you can. but as said before, if the cable is free just spend a weekend fidling. good luck.

ThanQ every body for all this input.   I must admit i had wondered if the clutch plates could possibly be contaminated from me previously using 20/50 n then going onto use 10/40. I changed clutch plates within a month of gettin her as i thought that may be the problem. I continued to use the 20/50 for a year or so afta that. Then I decided lets try proppa 10/40 as i was flushin engine thru n changin oil filter etc..    I also took on board wot "rusty chain" said. I did soak plates..in 20/50 the nite b4 fittin.! As to wether i fitted the plates rite!? Well to be honest i dont remember specifically. Knowing me,and as it was an unfamiliar job that i used mi haynes to it with, I probably did fit it rite. I have a good eye for detail,even more so if attemptin things I have never done before. I would normally lay stuff out on my floor as i take it out so it kan be replaced the same way. Even to the point of puttin bolts in the order they came out so they go back in the same holes!! Obssesive maybe..I call it methodical attention to detail.! If however i am mistaken bowt using the haynes then i would have bin rellying on how the previous clutch was fitted.   I do tend to waffle,sorry folks.   It seems like you all agree that i need to start wi basics. I need to change cable for new and set it up so that the freeplay i have allows the clutch to fully engage,this eliminates a number of possibilities. I need new plates(maybee springs?)and after soaking them in some better quality 10/40 mineral oil for bikes with a wet clutch(not a car with a dry one)..I need to pay attention to how i fit the plates so as to obtain correct and efficient seating.    I do appreciate all dis input,thankyou. For now i will start wi the new cable as it sounds like that will help,it certainly wont hurt.                                                                                                                                                                                

Ohh and i need to see if i got a notchy basket n all if i do go inside her again to change mi plates etc. If i do change the plates i will give you feedback on wot "Gloom" was sayin about the thickness differing in different makes off plates.    I dont have genuine "suzuki" plates in,just cheapo ones from the bike shop on the corner thats been there forever and unfortunatly has just had to close forever,recently!! I used to love that shop...   Just a kwick one on clutch plates while i am ear AGAIN.!! I know that one can buy upgraded pads n stuff for your brakes that make it stop kwicker n all that.! Well can you get any upgraded clutch plates which would give that extra bite..maybe do similar job to preloadin springs but less risky? If they arent available then maybe i just found a niche in the market!?   ..or should i just go with suzuki plates? I dont think i will mess with shimming my springs,it sounds like it could create worserer problems.   Thanxs eggen peeps. I hope to meet all or sum at future BM meets,you all got a gud "road crew" on ear from wot i seen so far n kant wait to party wi u all.                                                                                                                                                                                   

Personally I'd stick with the OEM clutch and maybe upgrade the back plate, which are a bit tinny. I doubt the extra 100 cc will be putting much extra power through.

If you do want to uprate it I personally like Barnett clutches but that's just me and I'm sure a lot of people on here could suggest other makes that they have used and found to be a good buy.  

genuine plates every time .. as for upgrades thers lots of stuff you can do ... you have pm                                                                                                                                                                              

Hey gloom..at the risk of sounding Silly-err than people allready know i am...!   I am not familiar with the term "OEM",pray tell wot this means pleaz?! I take it the backing plate comes with the clutch kit,how would i get a thicker one and wot part does it play in the opperation of my clutch? I have heard of barnet clutches but arent they hydraulic? If not hydraulic can i just put the plates from that in mine or am i just bin a total "plank" now?   Soz bowt all d kwestions! I kant help it,I was very inquisitive as a children n still am now..I love learnin new stuff!                                                                                                                                                                                

OEM = Original Equipment Manufacturer.

Nope back plates can be bought separately.

Off the top of my head I don't know if Barnet do a clutch for your bike but a quick google should tell you. What I'm suggesting is that you go with either the original parts or pick a well known after market supplier that is trusted.

Good luck with this and let us know if you get to the bottom of it. It's a pity you're a bit far or I'd nip down for a brew and a look at it. 

I did google Barnet and had a kwik look. They do all the stuff i may need,including baskets but i couldnt see any prices,will have to look again. They didnt have any for an 1980 GSX but they do have for an 1980 GS! However my haynes manual for the GSX describes the engine as a GS so i am assuming the parts will fit,I will check with them if it comes to that.For now i gonna get new cable and try n set it up properly as the handbook says.   I got a feeling in my bones tho that it may be the basket notched,or maybe like "Rusty chain" said I may have put plates in wrong. I got the bike off a mechanic dood tho n he said at the time the clutch was slipping,I just thawt it would be the plates so changed it..maybe he knew the problem.   I bin ridin her wi dis prob for 5years(carefully) n i gotta say the power i got aint bad even wi slippy clutch so just wanna sort it now. I know a man with a few GS1000's so i gonna c if he got a spare basket if i need one.   Fanxs again n if u ever over dis way rallyin or sumat gime a pm n we'l get togeva for a beard wag. I did my direct access course 3year ago so now i am legal i tend to go bit further affield rallyin so u never now i may c u at a rally your way on. I intend goin to sum BM rallys soon as sorted.                                                                                                                                                                              

probably too late now and you've fixed it, but make sure you have the actuator pushrod set right (under the cover where the cable goes in). There should be a removable small panel (3 screws) and you see the mechanism with a nut and screw in centre. Back off nut hand tighten screw in until it touches pushrod, then back out 1/4 turn. This is different to cable adjust at handlebar!

Hi there, if the problem is sorted then please feel free to ignore this but the guy who built my race bike engine said to me that he only ever uses castrol gps part synthetic oil to avoid clutch slip issues.
Also as said before make sure there is enough free play in the clutch cable to allow for tension under friction heating during riding, i thought i had plenty of free play but it was tensioning when warm and slightly pulling the clutch in.