GT500 Road Racer Project

tz375 · Post by **tz375** » Fri Nov 13, 2009 12:29 am

Dave Swarbrick in the UK manufactures exhausts which are generally very well made and highly regarded.

JEMCO makes two styles of exhaust for a 500 twin and one of them is referred to as the copy of Swarbrick pipes.

CJF · Post by **CJF** » Fri Nov 13, 2009 8:20 pm

Thanks for the comment two stroke brit. I'm not sure the jemco's are identicle to the dimmensions of the Swarbricks, but they do look close based on pictures i've seen. There are many comments on this board about swarbrick making the best pipes for racing, but they cost a lot. I have ordered a set of CR750 race replica pipes from him in the past and he does very nice work.

I just checked the measurements of my GT500 triple and they look to be 175mm center to center as well. Thanks for the info. I guess I'll troll ebay to see what's out there.

CJF · Post by **CJF** » Thu Mar 04, 2010 8:00 pm

Things are starting to move along at a quicker pace now that I'm at the assembly stage. I still have to rebuild the engine, get the electrics sorted and paint the body work, but that seems like a short list compared to all the work I've done so far. Here are a few pics....

Painted swingarm with new bearings. I had to bore these out after installing using a brake cylinder hone.

Painted engine cases...used duplicolor aluminum engine paint and clear

Newly polished forks just before the rebuild.

Painted frame and swinger, aluminum wheels, rebuilt forks, polished triple tree, steering damper and clip ons.

tz375 · Post by **tz375** » Thu Mar 04, 2010 9:01 pm

That is looking very sexy.

But what are the funny looking fork damper rods? Are they really a damper rod fork without a piston ring, or does that bottom bush/piston move and work like a shuttle valve and the "damper rods" are just the base for the springs?

I have never stripped a pair of those forks as you can tell from the comments.

diamondj · Post by **diamondj** » Thu Mar 04, 2010 9:25 pm

Hey Chris!

Good to see you working on the race bike again. I had though you put that on the back burner for the joys of parenthood. Any chance you'll be looking to do a school this year? I'm having trouble lining up a date to take an inexpensive race school. One of the guys on the Cafe Racer board may be setting up an event at NJMP in June that will offer a school....

tz375 - those are GT500 forks and the damper rod design is different from the rest of the GT series forks. If I am remembering correctly, there's no hole through the damper rod...
Jim

tz375 · Post by **tz375** » Thu Mar 04, 2010 9:52 pm

What you talkin' 'bout Lewis (Jim)- no hole in the damper rod ?

That's an odd design.

I have no idea how well (or not) they work, but there is room for improvement I suspect. A pair of suitable piston ring type rods and emulators and those forks could work like a charm.

johnakay · Post by **johnakay** » Fri Mar 05, 2010 12:58 pm

very clever work I must say.
whats that little clock on the left??

tz375 · Post by **tz375** » Fri Mar 05, 2010 1:17 pm

Dual EGT (Exhaust Gas Temperature) by Westach by the looks of things.

CJF · Post by **CJF** » Fri Mar 05, 2010 9:59 pm

I did have to scale back some on time dedicated to the project. Pretty much limited to nap time during the weekends

.

The forks are stock gt500. They are not known for great performance, but I stuck with them for now...figure this is something I can upgrade down the road. I did upgrade the springs to hyperpro spings from yss suspensions. You can't find direct replacement for the gt500, but they helped me find some custom springs to replace the 30+ year old springs.

That is an EGT guage, but I ended up replacing it with a CHT guage. It should do the job in terms of preventing any potential engine failure.

I'm hoping to get the bike ready for a track day this summer at the New jersey race track. I'm not sure about anything beyond that yet.

diamondj · Post by **diamondj** » Sat Mar 06, 2010 1:52 am

CJF wrote:I did upgrade the springs to hyperpro springs from yss suspensions. You can't find direct replacement for the gt500, but they helped me find some custom springs to replace the 30+ year old springs.

I'm hoping to get the bike ready for a track day this summer at the New jersey race track. I'm not sure about anything beyond that yet.

Hey Chris,

I'm running GT500 forks on my race bike as well. I don't suppose you have a part number for those hyperpro springs you could pass along to me?

Team Pro-motion and Motorcycle Excitement both run track days and race schools at NJMP and this may be my game plan for this year to get my license:

http://www.teampromotion.com/tpm.php?page_id=art

http://www.motorcyclexcitement.com/

"Tex" Mawby on the Caferacer.net board set-up a deal last year at NJMP for the "All Revved Up Festival". He is the region rep for Revvit leathers and he did a weekend event last June. Unfortunately, it fell on the weekend of my daughter's dance recital and I could not go. This year the WERA race in June falls on my daughter's recital weekend and Tex has said he won't schedule the weekend where it conflicts with WERA, AHRMA, USCRA, etc.. so there's a good chance I can make it this year. The thing that was cool about it was this:

We have worked out a pretty incredible deal for the All Revved Up Festival for Race Accreditation. Team Promotion will be offering A.R.T. Level 1 (Advanced Rider Training) $199.00 which will cover the school and offer safety gear (Leathers, Boots, Gloves......you MUST have your own Helmet). This is normally $249.00. They have about (25) 1-piece Leather Suits (various sizes) in the rental inventory. I highly recommend that you bring your own gloves and boots, as I think you will be more comfortable in your own gloves and boots. After successful completion of the School on Saturday, you are welcome to stay over and race with us on Sunday. We will offer the same A.R.T. Level 1 promotion on Sunday, however Sunday Race School students will not be able to race the vintage classes that same day. Team Promotion is an accredited school and their race licenses/certificates are accepted by WERA, AHRMA, USCRA, USGPRU, and the VRRA.

Jim

CJF · Post by **CJF** » Sat Mar 06, 2010 1:19 pm

Jim, The part number is SP-FO 2011 for the springs. I still need to make sure the sag is correct with the springs and can't do that until I have the bike put togehter with the engine in. They have a lighter spring rate than stock and are approx 3 inches longer. The increased length is around the same length as the stock spacer length, so the pre-load from the fork caps should be around the same preload as with stock.

They feel a little stiff, but that may be because I used 15 weight instead of 10. The guy at YSS said if the sag is correct 15-19mm, then the spring length is good and I can adjust with different oil weights if needed. I'll let you know how it works out.

Looks like there are a lot of date options at the NJ track for a track day class. I'm thinking I can get the bike ready by July.

CJF · Post by **CJF** » Sun Mar 14, 2010 5:44 pm

Finished putting together the bottom end, sealing up the cases and torqued everything down. One small problem...I didn't realize the oil pump gear is mounted on the inside of the cases

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

I had a pic from when I tore it down, but I guess i missed that and was too concerned figuring out where all the trans parts and seals went. I guess I will have plenty of practice pulling it apart and putting it back together. Never fails...I always have at least one big screw up every build.

tz375 · Post by **tz375** » Sun Mar 14, 2010 9:29 pm

It's a race bike so you'll get some practice stripping it form time to time. Better to get good and fast now.

I hate swapping cranks at the track, but it happens. In fact my son called me on his way back for the track to say that the TZ made a funny noise - turned out a crank had cracked and was machining out the cases. Messy.

But old bikes are easy to work on - thank goodness.

CJF · Post by **CJF** » Mon Mar 15, 2010 9:35 pm

The GT500 is real easy engine to work on...you're right. That's why i decided on it for the race bike. I took a day off after my blunder with pump gear and had the engine broken down and back together within an hour and a half. Now that is pretty fast and easy....and the best part is that i did it right this time.

CJF · Post by **CJF** » Fri Apr 16, 2010 8:59 pm

I've made a little more progress over the past month or so. I assembled the forks, had the rotor resurfaced by chris schuman on ebay (he is great to deal with) and started to assemble some of the parts on the bike. I'm now in the middle of assembling the engine. I added a pic below of the barnett clutch kit I picked up. They don't make them for the GT500, but I did some research and cross referenced suzuki part numbers to a part number barnett did carry...bingo..I now have a nice barnett clutch kit.

GT500 Road Racer Project

Its a roller again