Author Topic: Suzuki TR750 replica  (Read 7850 times)

Billy Dunn

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Suzuki TR750 replica
« on: November 08, 2017, 07:54:22 PM »
Just a brief update on my project. Making some progress, very pleased with the expansion chambers I was lucky enough to get Justin Roebury of this parish to make up for me, thanks again Justin, the fit is perfect!

Just starting on the engine rebuild. Hoping to have the bike running this spring and want to try parading it.

Sorry about side view! If someone can fix it please do
« Last Edit: November 08, 2017, 09:55:33 PM by Billy Dunn »

Billy Dunn

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Re: Suzuki TR750 replica
« Reply #1 on: December 12, 2017, 08:07:57 PM »
First trip to the dyno. Main accomplishment was getting it to fire up which it did with a bit of fiddling with the Electrix World ignition system. The system was fine it was just me with help from others understand how it works. The system is designed to mount on the right side of the engine and on this bike it is mounted on the left side so all instructions were for clockwise rotation and it runs anti clockwise. Not a big deal but at the time caused some issues. Bike also developed a coolant leak that shortened the session.

In the end the bike produced 87.6 HP at 8000 RPM. The goal is 90 to 100 at the rear wheel so was actually pleased,..........................it's bloody loud! Back on dyno on Thursday so fingers crossed.

Andy Guy

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Re: Suzuki TR750 replica
« Reply #2 on: December 12, 2017, 08:31:45 PM »
If you've fitted it the opposite way around will it not effect the map Billy?
Winners never qui

Billy Dunn

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Re: Suzuki TR750 replica
« Reply #3 on: December 12, 2017, 11:50:16 PM »
I talked to Peter at Electrix World and he explained the two magnets on the rotor give a North and South pole, there is only one spark per cylinder per rev, and to use the installation instructions for a three cylinder 2 cycle Kawasaki (H1 or H2). The advance map and high rev retard is contained in the CDI modules so independent from the ignition triggering system. This is my assumption so will follow up on your point to confirm so thanks for the comment.

An independent shop had cut the key way in the rotor to make things easier to assemble/ disssemble,  it was in the wrong location so that was the first stumbling block. In the end the bike ran reasonably well and the coolant leak was a minor issue. Hopefully more progress this Thursday. 



Kerry Wilton

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Re: Suzuki TR750 replica
« Reply #4 on: December 13, 2017, 06:32:22 AM »
If the rotor is a good fit on the crank taper it will stay put without a key (if it's more convenient to move the rotor to get the timing right) - been running Eelectrexworld and other ignitions on 350 TZ's like that for years. Lapping the rotor onto the crank is a good start.

Billy Dunn

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Re: Suzuki TR750 replica
« Reply #5 on: December 14, 2017, 06:33:53 PM »
Just a brief update. Back on the dyno today, coolant leak did not reappear and the bike ran well. We were able to re jet it and set the timing. Still rich at 11.5:1 and fairly stable for all three cylinders.

We ran the bike to 9000RPM, it made 98.6HP at 7500, this was a peak indicated reading then it dropped off dramatically by 25 hp at 7600RPM. Looking at rear wheel speed and RPM the clutch is starting to slip at 7500RPM. Will remove plates and glass blast both frictions and steels and try heavier clutch springs to try and get it to hold.

Made several pulls, the clutch problem became more evident when dyno pulls were back to back or as the clutch heated up. Got the best result after sitting for a while but was slipping at 98.6HP.

Pleased with the results. 

Kerry Wilton

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Re: Suzuki TR750 replica
« Reply #6 on: December 15, 2017, 05:12:48 AM »
Satisfying numbers, I'd wager. get the clutch sorted and some smaller jets and the numbers will translate into a quick motorcycle!

Billy Dunn

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Re: Suzuki TR750 replica
« Reply #7 on: April 05, 2018, 10:59:31 AM »
A little project update. I just got the fairing back from the painters, the bike is almost completed. Need to finish off the suspension system and set it up. Hopping to take it to Cadwell Park and give it a bit of a shake down in the next couple of months.

As I would like to parade the bike can some one take me through the required steps of having the bike accepted for intended purpose prior to just showing up at a track. Suspect a private PM is the most appropriate means to discus as the conversation would bore the socks off rank and file members. Thanking you in advance for your guidance.

Was unable to upload a picture of finished bike so will try later.

Geoff Wells

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Re: Suzuki TR750 replica
« Reply #8 on: April 05, 2018, 04:21:08 PM »
Hi Billy,

I race with the CRMC and they usually try to get in two parade sessions/day (Sat & Sun).  I believe that you will at least need a full UK bike licence and being a member of the club running the parade (day membership is usually available).  I simplifies entering if you have an ACU race licence (novice) or an ACU Parade licence.  Bikes that parade will still need to get passed by scrutineering just as any other race bike.  For definitive details it's best to contact the club for their individual requirements.  Look to the ACU web site for Parade licences and medical/eyesight requirements etc.

Quite a few clubs have parade sessions so you are not confined to the CRMC.  One thing to consider is that the term "Parade" does not mean bimbling around waving to the crowds, there will be some very fast bikes and riders circulating.

Love to see some photos of your TR750.  Here's my Seeley Suzuki T500 and a Road framed T500 that my rider Gary May is building.



Gary's build:



Cheers  Geoff

Steve Adlem

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Re: Suzuki TR750 replica
« Reply #9 on: April 05, 2018, 05:52:58 PM »
A little project update. I just got the fairing back from the painters, the bike is almost completed. Need to finish off the suspension system and set it up. Hopping to take it to Cadwell Park and give it a bit of a shake down in the next couple of months.

As I would like to parade the bike can some one take me through the required steps of having the bike accepted for intended purpose prior to just showing up at a track. Suspect a private PM is the most appropriate means to discus as the conversation would bore the socks off rank and file members. Thanking you in advance for your guidance.

Was unable to upload a picture of finished bike so will try later.

Geoff doesn't mention that if you do want to parade with CRMC, you will need a CRMC eligibility certificate, certification is cheaper to members. It is all on the website.  Since it is a 2 stroke it will be classified as a post classic, i.e. being post '67.

Billy Dunn

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Re: Suzuki TR750 replica
« Reply #10 on: April 05, 2018, 06:40:20 PM »


Finally got a picture up! Thanks for your replies gents I'll follow up on getting myself and the bike sorted for parading

Jenny Westwood

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Re: Suzuki TR750 replica
« Reply #11 on: April 06, 2018, 10:55:24 PM »
The bike looks great Billy.    :)