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New member - GT500 racer

Posted: Thu Aug 06, 2015 8:10 am
by Ravivos
Hi,
First, would like to introduce myself, my name is Raviv and i live in Israel.
been riding motorcycles for the past 20 years and currently owning a 97' TL1000s, 80' XJ550, 84 GSX750ES and the new purchase - a 77' GT500.
been working on bikes for quite some time now, and know my way around the workshop.
i really love fabricating metal and TIG weld my own exhaust pipes and mufflers.

the GT500 is the first big (well, not 50cc) 2 stroke bike i own, and its story is rather interesting,
this is the only GT500 here in Israel, and it has been sitting in a guy's living room (and shed) for the past 18 years, it was last owned at 84' and now... 31 years later, i manage to track down the owner and transfer the ownership onto my name (something equivalent to the US "title").

since it sat for so long, there are many things to do in order to get it road worthy, but it is rather unmolested and original, which is a good thing.
i would like to build a proper race bike that is road legal, so headlights and tail lights are a must...
i truly believe in doing things properly, so i would like to build a TR500 replica, with all the bells are whistles that comes with it.
Had some help over at caferacer.net, but i figured i'll ask here, as a more 2 stroke oriented forum, with much more experience with these bikes

so, here is the plan -
there was a big discussion about going single or dual rotors for front brake, your opinion? guess i can get the gt750 forks in order to get two calipers/rotors.
any suggestions for an aftermarket and decent caliper?

i need to perform a leak teat for the case to see if the seals are gone.
need to have a look on the pistons and make sure all is intact.
need to replace the complete chain and sprocket set, anyone got a link to a decent set?
need to clean the carbs... currently there is no airbox, any suggestion for good air filters? k&n? unifoam? how about rejetting the carbs to fit the new air filters?
i want to replace the spokes for the front and back wheel, as they are rusted, its 19' front and 18' back.

i contacted air-tech for their fairing, oh man this thing is expensive... any other source for these? if i wont find one, guess ill go with air-tech.

any other input will be greatly appreciated.
thanks.
Ravivos.
Image

Re: New member - GT500 racer

Posted: Thu Aug 06, 2015 9:11 am
by titan performance
Welcome.....you may be the only member currently posting from Israel.
I'm very interested to see how your race replica takes shape. We have built a number of cafe racers using the 500 as a base, but it's always good to see other people's ideas.
Keep the pictures flowing !

Re: New member - GT500 racer

Posted: Thu Aug 06, 2015 10:36 am
by Alan H
A mate has fitted early GT750 forks to his T500 so he could have the 4LS front brake. The complete forks and triple trees fit.
Suzuki GS1000 calipers fit standard late GT750/550 forks and you'll need a bigger master cylinder to work 2 calipers. I've used a GS1000 one as it is designed for those brakes.

Visited Eilat many years ago and called at the dead sea and Jerusalem as well.
Scuba was excellent. Israel is too.

Re: New member - GT500 racer

Posted: Thu Aug 06, 2015 12:39 pm
by tz375
Good to see you over here. Welcome. There are a few guys here that own/race/build T500 racers or TR500 replicas who have lots of good ideas.

Airtech are not cheap and maybe a half fairing might be a good place to start or find someone in Israel with a similar fairing (rare) that you could take a mold off - but that is likely to cost more than importing one.

There are other sources in Europe or the UK (not totally in Europe). Check with Jim Lomas, or Ragged Edge or Pete O'Dell or maybe French websites and see if there are better deals to be done.

Re: New member - GT500 racer

Posted: Fri Aug 07, 2015 5:40 am
by Zunspec4
Hello Ravivos,

Nice project, sure to be lots of fun.

Front end - Maybe consider a complete for swap from a modern bike. That way you get better damping, springing, wheels/tyre sizes, brakes etc. If you keep the originals re-build the wheel with an 18 inch alloy rim (lighter, better choice of tyres), same for rear wheel. Replace the std. calliper(s) with a modern twin/quad piston set using an adapter mounting plate (simple to do).

Engine - Complete strip down for new seals. The crank is pretty tough so it's very likely the main bearing, conrods etc. will be good. At least a hone on the bores, new rings if you can. Re-bore and new pistons is the best option using Wossner or Weisco forged pistons (Mitakas 2nd choice). Consider a new pair of Mikuni carbs VM32 or 34mm and inlets (all available, in UK at least). Mild, not wild , porting for a road oriented bike with a set of expansion chambers to suit (titan performance make a nice looking set of pipes and I'm sure he can advise on porting to suit),

Frame - TR500 style additional bracing. Decent set of rear shocks, lots on the market (Hagon etc.)

Fairing - I like the idea of a top half fairing, nice to see that Suzuki engine exposed. I use a Yamaha TD3 fairing on my race bike, not the same as the Suzuki TR fairing though.

Cash - Be prepared to see it disappear at frequent intervals :lol:

Cheers Geoff

Re: New member - GT500 racer

Posted: Sat Aug 08, 2015 1:03 am
by diamondj
Good to see you found your way to this board as well!

You can use a CR750 fairing from Nationals Fiberglass out of Ohio but I am not sure if he ships overseas.

https://www.facebook.com/pages/National ... 6197411868


Jim

Re: New member - GT500 racer

Posted: Sat Aug 08, 2015 11:49 am
by Ravivos
Thanks for all your help, guess i am the only poster from Israel...
bought a nice set of GT750 forks and will try to get two SV650 calipers, they are two pistons caliper and will clear the front spokes rather easily.
since i would like to keep the bike "period correct", an upside down front suspension will probably look a bit funny.
is there a direct bolt-on front rotors that i can use ? something out on a newer bike? a thinner, lighter rotors?
should i even consider going dual rotors or should i stay with a single one (unsprung weight).

will look into the CR750 fairing.
i have a half fairing of an old ducati, can probably make it fit but it wont be a TR500 :-)
but... there are still many things to do before fitting a fairing onto the bike.
and, if we are already talking about full fairing, i assume i will have to push-start the bike every time, since the kick-start will not protrude out of the fairing, any input on that ?

Allan, Eilat is a very nice place, a great place to have a vacation, single or family.

keep the information flowing, it sure give me a lot to think of.

regards,
Raviv.

Re: New member - GT500 racer

Posted: Sat Aug 08, 2015 1:48 pm
by Zunspec4
Hi Raviv.

I use a GT500 front hub on my T500 race bike, single disc (Hub will take a 2nd disc). The disc is an EBC one for the GT 500 & 750. In my case I asked them to make one with a 5mm thickness vice the 6.9mm of the standard Suzuki. Works very well with an AP Lockheed 2-piston calliper.

Cheers Geoff

Re: New member - GT500 racer

Posted: Sun Aug 09, 2015 2:49 am
by Ravivos
Hi Geoff.
sounds good, did you use any fork brace to reduce twisting under brake and bumpy road?
is the EBC rotor is something that was made specifically for you or is it an of-the-shelf product?
From what bike did the AP lockheed came off?

where can i get a new set of oil pipes and banjo for it? can i restore the old ones?
if i am on it, anything you guys think i should do/improve on the oil system? pump? piping?

i want to at least start the engine before it take the bike apart, and need the oil system up and running.
played around with the bike yesterday, it have good compression, need to go over the some of the electrical connections, maybe find a new switch and key for it (any input on this one?).

will post pictures as i go.
thanks.

Re: New member - GT500 racer

Posted: Sun Aug 09, 2015 6:22 am
by Zunspec4
Hello Raviv,

EBC produce replacement disc(s) for the GT 500/750 and these should be available from any EBC stockist. As you can't buy directly from EBC I opened a trader account with Brakes4U (20% discount) and via them EBC produced a 5mm thick disc to GT500/750 specification. AP Lockheed racing callipers are available new from a quite a few sources in the UK and I got mine from Dennis Trollop Racing for £130 apiece.

The forks on my race bike are Maxton Ceriani ( http://www.maxtonsuspension.co.uk/files/ceriani.htm )replicas with whistles and bells GP20 internals with adjustable rebound damping. These don't need a fork brace, I'm not sure how std. forks would benefit from a brace.

Photo of my front end set-up with AP calliper/EBC disc/carrier plate/Maxton forks. A real teaser to get everything aligned without disc hitting the fork leg and spokes missing the calliper etc. , but we got there in the end :up: . This basic set-up can be mounted to std. GT500 forks but requires a flat to be made to the lower fork leg.
Image

Cheers Geoff

Re: New member - GT500 racer

Posted: Sun Aug 09, 2015 7:43 am
by Coyote
SEXY :up: 8) 8)

Re: New member - GT500 racer

Posted: Sun Aug 09, 2015 9:02 am
by Ravivos
Sexy indeed!
made some calls, i can get an EXCEL 18" aluminum rim for a decent price, i assume i should go with WM3? or will the 2.5 will suffice?
what size and length of spokes do i need for an 18" rim with the original GT500 hub?

any input about the oil lines and banjos?

Thanks.
Raviv.

Re: New member - GT500 racer

Posted: Sun Aug 09, 2015 9:05 am
by Ravivos
Ravivos wrote:Sexy indeed!
made some calls, i can get an EXCEL 18" aluminum rim for a decent price, i assume i should go with WM3? or will the 2.5 will suffice?
what size and length of spokes do i need for an 18" rim with the original GT500 hub?

any input about the oil lines and banjos?

Thanks.
Raviv.
that is - engine oil lines, not brake fluid :-)

Re: New member - GT500 racer

Posted: Sun Aug 09, 2015 9:48 am
by tz375
SV650 calipers and CBR600F2 disks are a lot less exotic, but are a cost effective solution and they haul the bike down hard from over 100 mph and can chirp the front tire.

http://pinkpossum.com/GT750/phattrakka2/p5brakes.htm" onclick="window.open(this.href);return false;

Re: New member - GT500 racer

Posted: Mon Aug 10, 2015 9:17 am
by cyclocrossfool
good to see you made it over here. ill try and be more helpful. keep us posted, tom