Hello from SA. Any other GT750's around?

Hi guys,

Any other GT750's on the forum? :whistle:

I realize now these aren't the most popular kawa's around but I bought this kinda over the phone thinking it was a KZ750. But I got a good deal on it and going to be changing up everything on it anyways, so here I am. This is also my first old bike / project bike.

I believe the bike shares a lot with the KZ models, so hoping to find and share some good info. I already have a few questions.....

here she is

Welcome to the asylum :silly:

For some reason, the GT was fairly unpopular over here. Seems like a 3/4 liter shaftie is a brilliant idea, but what do I know??

No eBay APP ID and/or Cert ID defined in Kunena configurationSeems that folks elsewhere are content to brutalize them... :sick:

Welcome,

A GT750 is a KZ, The production model is (K)Z750P. They were most popular in Germany. Besides the shaft drive it has much in common with the (K)Z750R1, (K)Z750E, (K)Z750L and the KZ700A (US only model but many have found their way around the world).

There was an Aussie that checked in a few months back that had just acquired a GT750 as well.

Thanks for the welcome guys.

The basic idea is a cafe/brat style. Keep the frame, tank and engine and ditch the rest. Ditch the entire front end for a modern bike's gear. (ZX6/10 GSXR etc), Spoked wheels. Keep the old motor but with an EFI conversion (I have never worked or owned a carb vehicle in my life so I'm out of my depth there)

Based on my limited research thus far it seems the biggest question for me to deal with right now is the direction I need to go with the shaft. Personally, I kinda like the idea of keeping the shaft drive from a maintenance and cleanliness perspective. But I also want a wide spoked wheel for the back of the bike. Can't seem to find any other kawasaki bikes with both a shaft and spoked hub that I can work from.

The alternative seems to be a chain conversion, which seems do-able by sourcing an output shaft and a few other bits from a chain drive kz750 or GPZ750 perhaps? And then source a wider swing arm from a Z1000 perhaps. This option will allow a myriad of spoked wheel hubs to accomodate any rim.

The third option is a KZ1300 shaft drive swingarm and keep a kawasaki rear wheel. Will also have to see if the 1300 shaft can be made to work with the 750.

Is the 3.0" wheel from the Z1000's the widest kawasaki rear wheel in this same style? Will that accomodate a 180/190 rear tyre?

Hmmm have you considered what a chain conversion will cost you? I belive you will be much better of sourcing an other bike if you want to go for fat spoked wheels.
The BS34 carbs on the GT750 are easy to work with words that has never been used describing Kawasaki's EFI fuel injection. Except from die hard entusiast that can afford the hard to find parts.
No I would suggest that you should rethink the project. Based on keeping the shaft and the carbs as it will save you a lot $$
/A

Hi I turned one into a trike last year nearly finished but other projects have come in the way

Trying to use 35 year old FI with no new replacement parts would be crazy. On the other hand, a Megasquirt system might be pretty cool.

No eBay APP ID and/or Cert ID defined in Kunena configurationThanks for the comments guys. Definitely some food for thought. Based on some of the comments I may scale back on the build and get the bike running first the way it is now. Just don’t want to spend money on things like suspension, tyres etc only to have to change it later.

I’ll try to elaborate a bit on my thinking for some of the changes I want to make.

The wheels on these are 19F and 18R. 18x2.15 to be exact. What would be the fattest tyre I can fit on that rim? Seems to be a 120/130. If that looks decent I may keep it. Would certainly be the easiest solution for sure and I do quite like the spoke design of the enkei wheels. Widening the rim is an option too. I suppose the cost can be justified by comparing that to the cost of a different swingarm, chain conversion etc etc. The stock swingarm will need to be grinded a bit (it has some bracing) and then welded again to strengthen the bracing that will be ground away to clear a fatter rear tyre.

The rear wheel does look a little “tucked” in at the moment though. I’m guessing the only way to fix that is to change the swingarm. Is the KZ1000 ’79 shaft swingarm any longer? If the shaft is compatible with my motor then that would be an easy swap that fixes my length and wider wheel issues in one go.

As for the EFI. If the carbs can work reliably it would be cost effective to keep them. I’d have to learn about carbs from scratch though. For EFI I was planning to source an EFI bike’s ITB system and mate it up to a local engine management system, using a 60-2 trigger wheel. After adding a fuel pump etc I suppose it is a more expensive route, but can be very reliable with virtually no maintenance once done.


Looking at the motor last night (it’s opened right now), I saw one of the pistons has a damaged ring land. What do you guys think of this 69mm kit? The price seems really inviting compared to Wiseco. Can the stock cylinder sleeves (I think you call them barrels on a bike?) be bored out that much? Should I just go with stock replacement pistons rather?

What do you guys think of this 69mm kit? The price seems really inviting compared to Wiseco. Can the stock cylinder sleeves (I think you call them barrels on a bike?) be bored out that much? Should I just go with stock replacement pistons rather?

I'm not to sure for the KZ's but these "cruzinimage" piston kits are usually stock compression, they aren't a High Performance kit, I've seen them fitted to CB750 Honda's with a lot of success, great for the money, and they seem well made. If you after high comp pistons, send the seller a message to confirm one way or the other...

I know these are rare in SA, but you have a load of work and expense here and maybe something more complete and running would save you a lot of time and money.

Restoration costs usually exceed the bikes value - and that is on more 'desirable/valuable' models.

As has been noted here I'm not a big fan of the shaft drive GT's, but they were great designs and very durable. Despatch riders would regularly do over 100k miles on these. The City of London was virtually running on kawi GT 550 /750 and honda CX 500 back in the day - they were everywhere.

Check your frame carefully for rust, I was offered a Uk model for bits very cheap but I passed on it. The frame was literally rusted away on the sidestand side downtube -worst I've ever seen. I wish I'd taken a pic.

I started cleaning it up a bit today and digging into it a bit to see what exactly I'm dealing with. The previous owner started stripping the motor. He said it ran well, but it would "jump" or "slip" a gear under hard throttle at low speed/lower gears, but was fine in the higher gears. I can't see anything obvious wrong, the sub-assembly spins smoothly and quietly. Perhaps the primary chain has too much slack and needs to be changed? Visually it looks in good shape to me though, but I've never torn into a bike engine before.

Frame looks good. Couple of surface rust spots where the paint has been chipped over the years. Will be sanding them all down and repainting the frame.

Some pics: