TR500 replica build

Photos and progress of your restorations, even bikes you had but no longer own.

Moderators: oldjapanesebikes, H2RICK, Suzsmokeyallan

Post Reply
User avatar
ChrisK
On the main road
Posts: 121
Joined: Mon Nov 25, 2013 1:16 pm
Country: Australia
Suzuki 2-Strokes: T250, GS550, TL1000S, T500 race, GSXR400 race
Location: Perth, Western Australia

Re: TR500 replica build

Post by ChrisK »

[quote="ChrisK"

By the way, I think we may have found the issue causing the lean running on one side. It was always the left, so I swapped the carby and carby mounting to the right and the problem transferred to that side. All the standard leakdown tests had showed no problem in the motor itself but when I sprayed some carb cleaner around the carb intake mounting it suddenly stalled. So we are pretty sure it is the Cruizin Image carby boots that are leaking somehow. I have some genuine Mikuni manifolds and boot[/quote]

An update:
The new Mikuni manifolds and boots were installed and the problem persisted but to a lesser degree. Got to love these Sensor Connection CHT and EGT gauges, they show you what is going on before it gets expensive! To make it worse the problem kept transferring from the left to right and back again - WTF? Anyway, more copious spraying of carb cleaner and I finally honed in on the throttle cable entry into the top of the carbs. The cable that I had was a 90 degree entry guide that just sat in the top of the brass cup that comes with the carb. As the motor vibrated these were flapping around and I think, letting air in. So, I modified the cables and put a new screw in 45 degree cable guide and voila, the temps settled down. On the track next weekend so I'll give you an update after that - fingers crossed.
User avatar
ChrisK
On the main road
Posts: 121
Joined: Mon Nov 25, 2013 1:16 pm
Country: Australia
Suzuki 2-Strokes: T250, GS550, TL1000S, T500 race, GSXR400 race
Location: Perth, Western Australia

Re: TR500 replica build

Post by ChrisK »

I see it's a while since my last update. On the positive side we have now finished 6 races with no DNF. It's still work in progress but bit by bit we are getting the old girl more reliable. The temps are now much more consistent and so it is now more refining than rebuilding :) .
I am still plagued by front end chatter. The rebound damping had been maxed out so I have now gone up from 5 to 10 weight oil in the forks to see what that does. At the same time I have ditched one of the front discs, a bit of a double whammy but I am eager to see if this helps. If I can get it handling properly I think we'll take big chunks out of the lap times as at the moment I just have no confidence to chuck it in.
Back on track in a couple of weeks.
Suspensionking
Around the block
Posts: 89
Joined: Fri Jan 01, 2016 7:21 am
Country: Switzerland
Suzuki 2-Strokes: T500 Suzuki, AJR Bultaco, Honda NS475

Re: TR500 replica build

Post by Suspensionking »

Hi Chris,

i have been following your project as I also built a TR500 rep or at least someone else did most of he work. It sits in a Yam frame there are some pictures I uploaded they are also on Geoff`s post.
I am based in Switzerland but I race my Suzuki in the Spanish championship. I also run the cylinder head temp gauges and normal see temps of 184 to 195deg C depending the circuit and the day. This seems to be the optimum and the bike touch wood has not given any problems during last season and this. ( This season being one test day and one race meeting so far) We did have a problem balancing the the temperatures on each cylinder and one always ran 20 or 30 deg C cooler. We fixed that at the last race by dropping one jest size to 240 on the lefthand cylinder and now they are both at the same temp. I have also the Eddie Crooks special cylinder heads which are bigger with more fins, do not know too much about them as they came with the engine. Apparently they were made for the IOM TT. I work for a suspension company and can suggest a couple of ideas to try with your fork.
For the rebound on these early forks I think the 10w oil is better then 5 weight as the systems are not so sophisticated. However I think I red you had some special maybe more modern internals. Either way running 10w 0r 5 w will not change the rebound so much but the 10 weight does not separate so easily and will give a better feel in the corner when the front end is loaded and when you are under heavy breaking. It may well help to damp out some of your wheel chatter. I run early TZ350 35mm forks which are standard no external damping adjustment. I use 10W oil and run a single disc with twin piston lockheed and I sometimes could do with more power on the break if I get too ambitious but most of the time it works really well. I run 90/90 Avon front and have no chatter.
Well I hope some of this helps and great to meet you on this forum.
cheers
Eamonn
User avatar
ChrisK
On the main road
Posts: 121
Joined: Mon Nov 25, 2013 1:16 pm
Country: Australia
Suzuki 2-Strokes: T250, GS550, TL1000S, T500 race, GSXR400 race
Location: Perth, Western Australia

Re: TR500 replica build

Post by ChrisK »

Thanks for the interest in our project Eamonn. A bit of water has passed under the bridge since my last post! Firstly, we continued to the end of the 2016 season with good reliability and ended up winning the championship for our class, so that was pleasing. There was quite a break between the 2016 and 2017 seasons but unhappily our reliability has deserted us. In relation to the handling, we have made some significant progress. I am running 35mm GT550 forks with full Maxton GP cartridge internals and have settled on 10w oil but with smaller spacers for more sag. In addition I have ditched the old Koni shocks and am running some new Gazi units which seem to work quite well. I have also experimented with a shorter swing arm which make the bike turn quite nicely but is a bit unstable through full power turns.
On the motor side, the first Round saw the motor throw off the primary drive pinion which in turn made a bit of a mess of the clutch. That was fixed for Round 2 but then the gearbox decided to shed a few teeth on 4th gear.

Image

I am hoping for better luck when I get back on track in July for a tuning day as I want to run in and test a completely new top end which includes 5 port barrels and billet insert squish heads so I have my fingers crossed!
Zunspec4
Expert racer
Posts: 1087
Joined: Tue Dec 16, 2008 11:37 am
Country: UK
Suzuki 2-Strokes: T500R, SV1000S, TS125, Seeley T500
Location: Trowbridge UK

Re: TR500 replica build

Post by Zunspec4 »

Hi Chris,

Well done for last season and commiserations on the engine woes this year. Your work on the barrels and heads looks amazing I can't wait for you to tell us how it runs. My own race engine is almost ready for the dyno, after I have sorted the 38mm carbs so they actually have the same specification (came mis-matched but I have only just found out)

Cheers Geoff
User avatar
ChrisK
On the main road
Posts: 121
Joined: Mon Nov 25, 2013 1:16 pm
Country: Australia
Suzuki 2-Strokes: T250, GS550, TL1000S, T500 race, GSXR400 race
Location: Perth, Western Australia

Re: TR500 replica build

Post by ChrisK »

Thanks Geoff, I'm still running the 34's but I have the 38's there ready to bolt on and once I have this new top end run in and running reliably, that will be the next phase. The work that Ken Lavallee in Vermont USA did on the barrels is fantastic - all by hand, and my friend here in Perth, Allen Cook, took care of all the maching work on the heads and has done an unbelievable job. I am forever indebted to these two guys and I hope I can do their work justice out on the track.
My wife was indicating last night she might want to have a crack at riding the International Island Classic (Phillip Island) next year so it is tempting to take the old girl (bike that is) back over there as I have unfinished business from the disastrous effort in 2015. We'll see how the finances are looking :)!
We are lucky in having great support from Wiseco pistons, Cometic gaskets, The Sensor Connection for the gauges and sensors and our local Trakdayz for assistance with oils and tyres as this can be a very expensive hobby as you well know :lol:. And having 6 bikes in the team to fettle just compounds the issue although #1 son is sitting out this season and I haven't been racing Supersport, trying to concentrate on the historic classes we contest.
Zunspec4
Expert racer
Posts: 1087
Joined: Tue Dec 16, 2008 11:37 am
Country: UK
Suzuki 2-Strokes: T500R, SV1000S, TS125, Seeley T500
Location: Trowbridge UK

Re: TR500 replica build

Post by Zunspec4 »

Hi Chris,

I am very intrigued to see how your new engine works out power and torque wise. Have you thought about how the extra heat generated with the extra performance will be handled without water cooling. I think that heat might be a limiting factor on the air cooled T500 engine.

I would love to visit Australia, in general, and to Phillip Island for the International Island Classic in particular. Alex Sinclair who I sponsored with a modest amount during his Classic TT campaign a couple of years ago was at the International Island Classic this year riding a 750 TTF1 Ducati and had a whale of a time and some decent results. A fairly costly exercise though so out of my league unfortunately.

When I get my new engine onto the dyno I will PM you the results to add to your data, knowledge is strength :up:

Cheers Geoff
User avatar
ChrisK
On the main road
Posts: 121
Joined: Mon Nov 25, 2013 1:16 pm
Country: Australia
Suzuki 2-Strokes: T250, GS550, TL1000S, T500 race, GSXR400 race
Location: Perth, Western Australia

Re: TR500 replica build

Post by ChrisK »

Zunspec4 wrote:Hi Chris,

I am very intrigued to see how your new engine works out power and torque wise. Have you thought about how the extra heat generated with the extra performance will be handled without water cooling. I think that heat might be a limiting factor on the air cooled T500 engine.

Cheers Geoff
Spot on Geoff, we are hopeful the new head inserts will be very efficient cooling wise, they have the extra cooling fins as you saw and are mated to the original castings with silver heat transfer paste. In the brief running it's had, the cylinder head temps looked very encouraging but of course it hasn't been up to full power yet so we'll see. Once we have proved the concept I think it will be time to unveil the sneak previews you saw to the world :lol:
Zunspec4
Expert racer
Posts: 1087
Joined: Tue Dec 16, 2008 11:37 am
Country: UK
Suzuki 2-Strokes: T500R, SV1000S, TS125, Seeley T500
Location: Trowbridge UK

Re: TR500 replica build

Post by Zunspec4 »

"ChrisK - Once we have proved the concept I think it will be time to unveil the sneak previews you saw to the world :lol:
When you do Chris let me have the first refusal on a set :up:

Cheers Geoff
diamondj
Road race school
Posts: 785
Joined: Tue Oct 14, 2008 11:00 pm
Location: Wharton, NJ USA

Re: TR500 replica build

Post by diamondj »

Zunspec4 wrote:
"ChrisK - Once we have proved the concept I think it will be time to unveil the sneak previews you saw to the world :lol:
When you do Chris let me have the first refusal on a set :up:

Cheers Geoff
Can't wait to see the extra port cylinders and cylinder heads as well.

Had a though on your chatter issue but may be way off base - the stock T500 gets "twitchy" when the front end is raised or the rear end lowered. You switched to longer GT550 forks but I am sure this is partially off-set by the 18" front vs the stock 19". What is the length of your current rear shocks and have you considered lowering the front of the bike by raising the forks in the yokes 1/4"?

Jim
User avatar
ChrisK
On the main road
Posts: 121
Joined: Mon Nov 25, 2013 1:16 pm
Country: Australia
Suzuki 2-Strokes: T250, GS550, TL1000S, T500 race, GSXR400 race
Location: Perth, Western Australia

Re: TR500 replica build

Post by ChrisK »

Thanks Jim, Yes we have been experimenting with ride height, I now have a set of shocks with ride height adjustment so I can raise or lower the rear to some degree. I think one of the major issues was lack of static sag which has since been corrected by installing shorter spacers in the Maxton forks. I also have run a shorter swing arm which has made it a bit twitchy but on the last time out the front end was definitely better behaved!

The last episode has been a broken gearbox though.
Image

We are back on track on the 15th of July for a tuning day so I'm hoping we can get this new motor run in and see what it can do :)
SpecialK
On the street
Posts: 18
Joined: Tue Jun 23, 2015 4:37 am
Country: USA
Suzuki 2-Strokes: RM100 RM125 RM250 CR250 T500
Location: Vermont

Re: TR500 replica build

Post by SpecialK »

Hello Suspensionking,
I work with ChrisK on the engine development for his T500. I'm always looking for data that I can use to give me an indication of how our bike is comparing with other T500's. I noticed you provided some CHT (cylinder head temperature) data to ChrisK and this caught my eye. It appears that our bikes have very similar readings. The picture I've included is data I've collected from ChrisK's outings as I use this to help guide us in the setup of our motor. The point where we were clean of air leaks, etc (ChrisK describes above) we can see how our thermals started to stabilize (the green windows). Essentially we've found that we run between 180-200C which for the most part agrees with your feedback. These data are from a stock hemi-head dome design as at this point we did not yet have our squish heads installed. Our plugs had a nice cocoa brown color (perhaps a tad on the rich end yet ran very crisp). The last few data points you can see temperature trending downward and that is because at this outing, the air density was decreasing as measured on our A/D meter but we did not have time to change jets to compensate. Thank you for sharing your experiences in this forum!
SpecialK
You do not have the required permissions to view the files attached to this post.
Zunspec4
Expert racer
Posts: 1087
Joined: Tue Dec 16, 2008 11:37 am
Country: UK
Suzuki 2-Strokes: T500R, SV1000S, TS125, Seeley T500
Location: Trowbridge UK

Re: TR500 replica build

Post by Zunspec4 »

Hi SpecialK,

I Thanks for the CHT data. I have a pair of TTO (sensor under the plug) gauges. I only have data from the dyno runs with the "cooking" engine. The Max I saw was 145 (ish) degrees C. I can't tell you what they run at during racing as Gary could never remember exactly what they were reading (too busy riding :lol: ).

Unfortunately the gauges are now reading a 20 degree difference during runs on the new engine, and the head readings reverse if you swap the sensors around. I think I have a bad sensor, although whether it's the low reading or the high reading one I don't know. What EGTs are you using as I believe they probably give a better indication as to the running health of the engine.

Cheers Geoff
SpecialK
On the street
Posts: 18
Joined: Tue Jun 23, 2015 4:37 am
Country: USA
Suzuki 2-Strokes: RM100 RM125 RM250 CR250 T500
Location: Vermont

Re: TR500 replica build

Post by SpecialK »

Hi Geoff,
We have plans to monitor both the CHT & EGT of the motor. The CHT is only one piece of data that we can track as our gauges has a "MAX" feature that provides and stores that info and the rider does not need to look at the gauge (thank god!). These sensors are the "under-the-plug" style. I'm glad Gary is minding business in front of the bike! lol. The CHT/EGT sensors are from "The Sensor Connection" (one of our sponsors) and are clearly the units to use for tuning the main jets correctly on the bike. To do this properly, we need to install our "Innovation" datalogging electronics which sample the EG temps every 0.1 sec. With this, we can build a thermal profile (bell curve) of the EG and then determine which jet size (coupled with the air density reading) is appropriate for max performance (ie. peak temp - 100C). We have not yet had time to install this so we just log the max EGT temps for now. For now the CHT is being used to help determine what is the working temperature of the motor under load when jetted correctly. Once we get going with the new multi-port/squish head top end, I'll be very interested in seeing how the thermals change. Chris and I have agreed to share what we've learned on this project with the community once we have things sorted. Thank you for your feedback!
Ken
You do not have the required permissions to view the files attached to this post.
Zunspec4
Expert racer
Posts: 1087
Joined: Tue Dec 16, 2008 11:37 am
Country: UK
Suzuki 2-Strokes: T500R, SV1000S, TS125, Seeley T500
Location: Trowbridge UK

Re: TR500 replica build

Post by Zunspec4 »

Hi Ken,

Thanks for the feedback on gauges. The TTO type I have will also record the Max temp reading but in this mode they alternate between running temp and Max reading every 15 seconds which is rather disconcerting if you see 100c one look and 145C the next. As Gary didn't look at them anyway I guess I should have taped them over and looked at the results in the pits :lol:

Sharing data and knowledge is something I also have no issues with, It's not like we are guarding our secrets from world championship rivals :D

Cheers Geoff
Post Reply