1983 GS750E Progress:

[MK3Brent]

Hey, friends.

I figured I'd post a little thread here updating some neat stuff I finished up over the last couple weeks. I still need to get the wideband O2 running on the bike, but should have that done by the weekend.

I was working really hard trying to finish a few add-ons to this bike before last weekend, but as luck has it... I had clutch issues at the last minute.
The clutch basket pressure plate boss has a stripped threaded hole, so I'm replacing the entire assembly with new Suzuki parts. Going back to Suzuki pressure plate springs, and ditching the Barnett stuff.

I really respect the opinions and suggestions I have received here on my other bike thread, so I figured I'd get some more input for this one.

What I'll do here is write out what I've done already, and leave it open for suggestion for further upgrades.

Modifications:

Ignition:
Dyna-S ignition (Deleted ignitor, stock coils, wires, NGK plugs .032" gap)

Suspension:
Suspension Front - Front forks are from an 82' E, removed stock pre-load spring and spaced the damper 2.5", these forks have schrader valves for air pre-load, currently have 0psi until I get it running soon. Sag in the front is approximately 30mm.
Suspension Rear - Rear schocks are Ohlins SU-143, sprung for my weight.
Rear swing arm - GS1100E, I drilled and reamed the frame for the larger pivot bolt. All new bearings/seals.
Stock anti-dive units were cleaned and rebuilt, a new front end is in the plans. Maybe in a couple years.
Standard clip-ons, can't remember where I got them.
Stock gearing, fresh 630 chain. I'll probably convert when these sprockets are worn out.

Frame:
Few misc. features deleted from the frame such as battery mount tabs, and other misc. tabs.
Rear tail section is cross braced with 1" x .125" angle steel. (Serves as a battery mount as well.)
Rear-sets from a 2004 GSX-R. The brackets I fabricated out of 1" C-Channel steel .125" THK, and a milled slot.
I turned down some carriage bolts from 316SS such that the head of the bolt slides nicely in the channel, and allows adjustment for proper riding posture.

Brakes:
Rotors, calipers are stock.
Pads are NOS.
Brake lines are teflon lined SS braided.
All brake components are rebuilt and cleaned.

Carbs:
53mm Mikuni CV carbs
Dyno-Jet Stg. 3 with adjustable needle jets
Mikuni 70mm velocity stacks, aluminum.
All cleaned and rebuilt.

Exhaust:
Vance Hines, 4-1. (rest of exhaust not pictured.)

Electronics:
Innovate XD-16 wideband O2 sensor and gauge/data logger.

Battery:
Odyssey PC680 sealed.

I think that's about it... Running a mis-matched tire right now. Contemplating a nice new set for the season, but haven't done anything yet.

Here are a couple pics. I'm going to clean it up a little more here soon. I have a CR-750 fairing coming for it with in the next couple weeks. Air Tech is currently making it for me, so I'll see how much I like it when it's here.

Anyway, have a look.
If something I have done is down right stupid... please educate me.
As always, I'm here to learn.

One of the sliders before painting:

 

[JAG]

That's pretty.

 

[eil]

Looks pretty nice. Interesting that you've left the anti-dives, they seem to be one of the first things that people delete even when they plan to keep their bike relatively stock.

 

[SVSooke]

Hmmmmmmmm.....that's not an 83 750E,they where the new for 83 third gen design.Not busting your chops on that ,depending where you are it could be a registration thing.Only other thing I query is what eil did,why keep those ineffective anti-dive units.

 

[MK3Brent]

Hmmmmmmmm.....that's not an 83 750E,they where the new for 83 third gen design.Not busting your chops on that ,depending where you are it could be a registration thing.Only other thing I query is what eil did,why keep those ineffective anti-dive units.

It is a registration thing. (on the vin plate)

As for the anti-dives, mine work well... so I dunno what to say about it.
I do plan on doing a new front end next year though, so we'll have to research which route to take.

 

[kimjay]

Love it, looks really nice

 

[MK3Brent]

Little clip of the bike running:

http://www.youtube.com/watch?v=ZKL01gu16F8

 

[chuck hahn]

Looks good. Keep the pics and updates current.

 

[63ronin]

Wow... I wish my projects looked that cool...

 

[Nicolas1982]

Cool project.I love it!! Are You planning to paint the tank? I'd say leave it as it is
What's the size of the tyres (front/rear)?

 

[MK3Brent]

Thanks guys.

Tank has been bare for about a year and a half, and I think I'll keep it. Probably brush it once more, then do something to seal it.

Rear tire is 4.00-18
Front tire is 100/90-19

 

[MK3Brent]

Hmm..

So with my new synthetic oil, the clutch is slipping like crazy.

Think I screwed up? Should I go back to dino oil?

The clutch plates were in tolerance for wear, and I replaced the driven plates with non-warped ones. I took almost all pre-load from the cable so it's not engaging the clutch, and it slips in first gear really bad.

Sucks, because that was some expensive oil.

 

[Guest]

Hmm..

So with my new synthetic oil, the clutch is slipping like crazy.

Think I screwed up? Should I go back to dino oil?

The clutch plates were in tolerance for wear, and I replaced the driven plates with non-warped ones. I took almost all pre-load from the cable so it's not engaging the clutch, and it slips in first gear really bad.

Sucks, because that was some expensive oil.

Probably got another problem besides the oil. I've been using 100% synthetic oil for years, no problems. Stuff I use is $9 a quart.

 

[MK3Brent]

Probably got another problem besides the oil. I've been using 100% synthetic oil for years, no problems. Stuff I use is $9 a quart.

Yeah, I agree.
Just swapped out the clutches again with some other plates.
Going to clean the oil off the drive plates and measure again. I think maybe the friction compounds in them are just too old and done, regardless of their physical size.

I have a lot of spare parts, so like I said... I'll swap out the clutches.

PS, I haven't taken out the basket before on one of these bikes. Are they interference fit? Or should the basket come right out once the nut is removed?

I have the proper tools to do the job, but I'd love to know in advance.

Thanks.

 

[CivilRock]

I don't think you need to remove the basket to swap out the plates. Just lay the bike over, pull the cover, pull the springs and take out the plates one by one. Have your phone handy and take pics as you go so you.... wait, you're an engineer. Never mind.

I recently did the same thing and finally realized that I had just a hair of tension on the cable. It felt loose but it changed just a little with some heat. And would start slipping. Real rookie move for a seasoned veteran.

If that's not it for sure, you can add shims (washers) to the springs, or swap out the springs for heavier ones.

I had to buy a new clutch (one broken friction plate) and I got some HD springs. They were super heavy and fatigued my hand. So I put in 3 of each. Then I realized that I didn't need them at all with my stock hp and went back to the stockers.
While you have the plates out check them for glazing. You can also give them a freshening with some 600 grit. Also have the manual handy to make sure you or a previous owner didn't put a washer in wrong or something.

I lay the bike over so I don't have to buy $50 of oil every time I go in there to make an adjustment.

Kevin

 

[CivilRock]

Whoops. You've had the plates out already.

Basket should come out with the nut removed. There's a spacer that comes out first then it can move over enough to come out.

 

[CivilRock]

Sorry to babble on.

Also check the synthetic you're using. You want get one without the super slippery friction modifiers. I can't remember all the specs, it used to be just get the Mobil 1 with the red cap. But they don't sell it anymore.

It's just hard to figure out because there's 1M people with 1M different ideas on the subject. It gets nauseating. Now I just buy Dino oil and change it too often.

Kevin

 

[blowerbike]

an 83 750E/ES in the states have a worm gear in the sprocket cover.
make sure it has a half turn of free play or it can be holding your pressure plate from clamping your clutch back 100%.
and i'm glad to see someone post about being within spec but maybe the plates are hard from heat cycles...i have preached that till i gave up on people listening.
glad you mentioned it

 

[MK3Brent]

The reason I mention the basket, was because I had a stripped pressure plate stanchion. I was able to re tap it for a 1/4-20 unc to me rolling again. Meanwhile I have a good condition basket replacement.

Thanks Kevin.

Looks like this time might have been the trick. Need to test ride.

 

[MK3Brent]

I suppose I should update this thread to resolve some questions if anyone searches for similar issues concerning the clutch.

I'm not quite sure what the issue really was. I believe that it was a combination of some slightly warped drive plates and un-lubricated driven/drive plates were causing my problem.

How I resolved the issue:
I swapped over a new set of drive discs that were true and flat, and also replaced the driven discs.
This alone didn't solve the issue. The bike would still stall once I dropped it down into first gear.

So with the bike on the center stand, I would drop down into first gear.
The rear wheel would begin spinning, even though the clutch was depressed.
I then eased onto the rear brake while listening to the engine speed fall. I then supplemented throttle with the loss in RPM from the dragging of the brakes.

I kept this up till eventually it loosened itself up enough to not lose RPM when applying the rear brake.

So perhaps it was just a lubrication issue in the basket. Everything is fine now. Slips fine with the wheels firmly on the ground and dropping it down into 1st.

------------------

Here is also an update on the wideband, and tuning my carbs:

The meter is pegged at cruising speeds.

At WOT, I'm actually right where I want to be mid 12s-13.

I just need to either play with the jet, or possibly adjust the air screws... but that will lean out my WOT range too.

Best to start with the jet.

My wideband was pegged 9:1 AFR while cruising, and idle.
While I wasn't sure if the gauge was accurate, I removed the plugs to inspect.
To my surprise, the plugs looked "okay." Not excessively rich or perhaps oil coated/burnt.

I removed the carbs and lowered my needle jets from the 4th notch from the top, to the 2nd notch from the top. (Dynojet kit needle jets.)
Also, I screwed the fuel mixture screw down to the full seated position. (Max lean.)

I re-installed everything, warmed up the wideband, and started the bike.
Now as predicted, the bike needed the choke to idle and I recorded the observed AFR. (18-19:1)

I then proceeded to dial out the fuel mixture screws 1 turn at a time.

AFR's are being measured at idle speed. 1100rpm or so.
1 - Turn from full seat resulted with an AFR of 17:1
2 - Turns from full seat resulted with an AFR of 16:1
3 - Turns from full seat resulted with an AFR of approximately 14.7:1 stoic.

AFR's are acceptable now through the rev range.
I'm going to continue logging and fiddling to get things the best I can.

I just wanted to share that the wideband has probably been the best modification for this bike yet. It has made my life so much simpler while trying to trouble shoot. I can really take advantage of the 70mm velocity stacks. Low end grunt is much more noticeable. I wish I had some baseline hp/tq readings before all the changes during the years.

Next up, will probably be to either get some extended front brake lines or replace the entire front end totally like previously discussed.

One last thing:
A few months ago I purchased a pair of U-Clear's HBC 200 helmet communicators.
These things are really awesome. If you ever ride with a friend or something, it's really useful to talk or w/e while riding.
When you're riding alone, you can sync it to your phone or bluetooth music player and enjoy your ride with some tunes.
The benefit of it, is all you need to do to mute or stop the music is tap the side of the unit on your helmet. (Nice feature.)

Anyway, thanks for all the help as always guys.