1984 GSX 750 EF down under

[Loccoli]

Hi all,

Not really a restoration, just a freshen up, but for me I may as well be building the pyramids.
After buying an '84 GSX750EF last year, I've finally got time to put some work in and get it on the road. I don't really know what I'm doing so this place is a massive help - I would never have tried rebuilding carbs without an experienced friend looking over my shoulder, yet here I am pulling them apart and really enjoying it thanks to all the resources here and on related websites. So a huge thank you to all of you who put time and effort into helping complete strangers out!

When I got the bike, it started and ran fine - I rode it for about 20 mins and all seemed functional, but I've previously only ridden single-cylinder offroad and adventure bikes, so I wouldn't have noticed any minor jetting issues and the like. So I'm hoping that with some attention to all the key areas highlighted on GSR that it will be good to go once I'm done. There is a yearly bike event at Easter that I'm hoping to get the bike to and ride on the track (it's untimed and non-competitive, just a way to get old bikes out and about). It's good to have a deadline to work to, even if I fail. I'm a pretty slow and steady worker with this stuff.



This is my to do list:
Rebuild carbs - halfway there (all fresh seals & o-rings waiting) - I have some questions about this below...
Clean up surface rust on frame and touch up paint - pretty much done except for a sand and another coat on the visible portions of the frame.
Install s/s braided brake lines and disconnect anti-dive
Check/adjust valve clearances
Test electricals -this I really have no idea and am a bit hesitant, even after reading through pages and pages of stuff on here
New exhaust - I had tried repairing the stock system but it's too far gone - have a Marving system on the way (woops, there goes the budget!)


Once the budget recovers from the exhaust, I'll get new springs and the fork legs could do with some attention.

Anyway, I've dismantled the BS32 CV carbs and found the following jetting. The stock jetting is in brackets.
Pilot jet 40 (stock 37.5)
Pilot air jet 155 (165)
Main jet 120 (117.5)
Needle jet Y-7 (Y-6)

Note, these stock jetting figures are from the only manual I've found, which is for a 1983 GSX750E & ES. Presumably these should be the same for my '84 EF as all else seems identical on the bike - can anyone out there clarify this?

The carbs have clearly been taken apart before as not only is there anti-seize on some bolts and wear on the screw slots in the jets, there were also 2 out of 4 and 3 out of 4 pilot jet o-rings and washers missing completely! Easy thing to lose I suppose!

So my question is, assuming my stock jetting figures are correct, why has the bike been tuned richer than stock when it is completely stock? And is this possibly gonna be in my favour when I put the new and presumably freer-flowing exhaust system on? Should I make changes at the air end, like leaving the airbox lid off as I've seen someone mention?

When I had it running briefly, all electricals seemed to work as they should. I've seen plenty written here. Is it worth installing a series R/R as a preventative measure? Of course I'll work through testing and cleaning connections, but curious if I can avoid some heart ache with a simple job.

I'll keep posting updates and include more pics once I can get back on my computer and work out image hosting.
I can't wait to ride this thing

 

[Guest]

Jetting is the same as '83. With the stock airbox on, it should run fine with the aftermarket pipe. I've had a yoshimura on mine since '84.

 

[Guest]

And yes on the series r/r.

 

[Loccoli]

Thanks!
So a previous owner has jetted it richer for some reason... Well I'll run it how it is and see I suppose.

It's stinking hot today, so probably only manage an hour or two in the shed. Finish up the painting on the frame and then maybe I'll go shopping for some tools I need.

That's a lovely looking ES, King

 

[Guest]

Thanks. One of these days i'll have to set up a account with a new photo hosting site (not photobucket) and post up some new pics. It doesn't look like that anymore. The only pieces that are original are the frame, fuel tank and the bodywork, and the seat. Has a short stroke gsxr750 ('88-'89) motor, and its pewter gray/dark grey. Has a 180/17 Shinko drag radial on the rear, because i e.t. bracket drag race it.

 

[Guest]

BTW it's -20 degrees F here. So cold that i won't have to go to work tonight....

 

[Loccoli]

Only had a few hours to dip one set of carb body and float this weekend, but the Yamalube carb dip did a pretty good job. Only problem is there's not that much in a bottle to do more than one carb at a time. Should get em all done next weekend.




Didn't have much time because I went on a road trip to buy this:




Had one when I lived in the States for a year and always wanted to get one and this came up at a good price. Lovely sounding beast.


But back on topic...
Frame looks decent for a brushed on touch up job. Don't have any before pics so you'll have to trust me it was spotted with surface rust, especially the front.

 

[Guest]

Welcome along, always good to see another Aussie join!

The EF's are nice bikes for sure, should see you well when all done up. That Yamalube carb cleaner is good stuff too, have used it myself with great success.

 

[Loccoli]

Thanks Pete.

Been following your Katana build thread, can't wait to see it all together, you're doing a great job. My best mate's dream bike is a Katana and I'm pushing him to save up and get one (mainly so I can take it for a spin!)

 

[Guest]

Cheers mate, keep pushing him, they're fun bikes to ride

 

[Loccoli]

Finally back GSX work. I had a 2 week off road adventure in Tasmania so prepping for that took all my time.

Got back to rebuilding the carbs - those tiny holes in the float bowl were clogged in 3 out of 4 and took ages of poking around with wire and carb spray to clear. Almost ready to put them back together and move on to other jobs, but a quick question. Why does one of my carb bodies have much worse white oxidisation on it than the others after dipping? And is there an easy way to clean it up a little?
I tried vinegar as per someone's suggestion, but no luck. I'm not that fussed about appearance because you can't really see the carbs on the bike, but it's annoying that one is quite bad - it wasn't this bad to start with. For the record, I used Yamalube carb dip.

Bottom left in the pic, carb #4



Any suggestions?

 

[londonboards]

Looks like that one is an outside carb. Might have been exposed to the elements more than the others and have a rougher surface as a result.

After cleaning in an Ultrasonic (use one if you can) I boil mine up on the stove with a little lemon juice or lemon washing up liquid just to get all the impurities out of the pores of the metal.

Then as soon as you take them out, shake the excess water off and spray the outsides with WD40 and wipe down.

Or have them vapour blasted for the ultimate finish.

 

[londonboards]

This is really helpful:

[url]https://thexscafedotcom.files.wordpress.com/2014/06/mikuni_bs-cv_carburetor_rebuild_tutorial.pdf[/URL]

 

[Loccoli]

Thanks mate. Yeah it is an outside carb.

I've been following that PDF guide all along, so helpful to have it spelled out!
All the passages are clear, fresh o-rings are here, just putting them back together. I ended up using some oven cleaner to tidy up the bulk of the oxidisation on the outside carbs. It's good enough for where it sits under the body work, but nowhere near as shiny as yours!

 

[Loccoli]

Can't believe it's been almost a year since I posted here. The GSX sat lonely and unloved for a while, I had a couple of exhibitions last year that took up a lot of my time and I got off track with the old Suzi between that and doing some work on the other bikes.

Anyway I'm back on it now. I've given myself the deadline of Easter to get it on the track (non-competitively) at the Broadford Bike Bonanza.
Carbs are rebuilt and bench-synced. A mate with a vacuum tool will help me sync em properly when I'm ready. Valves are adjusted and the two exhaust bolts that had seized and snapped have been drilled out and helicoiled.

I have a SH775 from Nessism (thanks mate!) and just picked up the Triumph harness that's supposed to plug right in.

Front brakes are all rebuilt with stainless lines and a fresh lick of paint. Working on the rear brakes but the master cylinder is pretty rough.
Does anyone out there know of a bolt-on rear master cylinder replacement from a newer bike? I see a lot of GSXRs use the same rebuild kit which suggests the internals are the same, but not sure if they'd bolt on.

Otherwise not a huge amount left to do. I'll try to post some pics soon.

 

[Loccoli]

Here are some progress pics from the last week or two:

Brakes getting taken apart, painted and rebuilt with new seals, pistons, stainless lines, etc.

Not the best job but looks much nicer on the bike.

As for the r/r, it seems if I turn the cdi upside down it creates just enough space for the SH775 in the stock r/r location. The holes in the brackets are a mm or two shy so I'll try some incantations to stretch it out.
I need to be careful of edges of wires with the harness running to the top of the bracket instead of the bottom but should be able to package it safely. Only other concern are the cables from the shock rubbing on the r/r.
This is it mocked up:

I can put some foam tape on the corners and/or a sleeve of some kind on the cables.
I may end up buying a YSS rear shock down the track so those cables wouldn't be an issue then.

Hopefully I can get the r/r wired in today.

 

[Loccoli]

Like a lot of people, I've had a bit of extra time the last couple of weeks, so I finished off the GSX (for now). There is still a bit of cosmetic work to do, but it runs like a dream and everything seems to work. The worst part of all this is that I have this lovely bike sitting here raring to go and I can't in good conscience take it out for a spin. I've only been able to ride it around the block a few times to make sure everything worked. I will definitely be taking it to the shops when I only need a couple of things, as that will count as an essential trip!

Here it is:

]

The rec/reg went in without a hitch. As previously mentioned, mounting the CDI upside down made enough space for the SH775 to fit in the stock position. Some gentle persuasion (hammering the ridges of the bracket) made the original bracket line up nicely with the holes in the new r/r.

I rebuilt the brakes and added braided steel lines - unfortunately the rear line was 10-20mm too short. It would reach if it were "floating" but not routed through the loops on the swing arm, so I've put the rubber line back on the rear until I can get HEL to send a replacement. The rubber ones are in fine condition. They were probably replaced by the PO.

New Pirelli Sport Demons to replace the brand-new looking 11-year-old Sport Demons that were on it.

Down the track I will probably rebuild the forks and use the opportunity to paint the fork lowers. This will wait until I can afford new springs and rear shock, and possibly cartridge emulators.

Otherwise there are some cosmetic things to do like clean and polish the wheels, but at this stage I just want to ride it! It's such a bittersweet feeling to have finished the work I wanted to do on the bike but not being able to go for a good ride!

Thanks to all of you who have shared knowledge on this site, I have spent many hours poring over threads getting my head around things I didn't understand or know how to do, and it's paid off. This is my first project and first straight roadbike and it's safe to say I wouldn't have been able to do it all without this site! I know it's not a big project by the standards set on here, but it was for me! Special thanks to Nessism for supplying me with a tested r/r. I hope it will prevent me having to deal with electrics too often!!

It sounds really nice by the way. A bit loud but not Harley narcissist (Harlissist?) level loud. Let me see if I can post a video...

Stay safe out there folks!

 

[Loccoli]

Click the picture for a video

 

[GregT]

Welcome to the site.
That jetting is stock. Don't know what manual you've looked at but it's "rest of world" jetting. Aus, UK, NZ got that jetting.
Suzuki often varied jetting between markets according to what emission standards they had to achieve.

It was very apparent a couple of years later. The early GSXR750 export versions with slide carbs had totally different jetting to the Japanese home market bikes. And the US market got CV carbs....

 

[Loccoli]

Thanks Greg.

Yeah I worked that out once I got hold of a service manual! I also discovered that our wheel and tyre sizes are different to the rest of the world. 120 front instead of 100 and 130 rear instead of 120. I was home sick one day a while ago and thought I might order tyres. Glad I went out to the shed to double check before I did and didn't trust online specs. Lesson learnt!