Triton wheel size poll

grandpaul

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All you current and former Triton owners, what size wheels are you running / did you run?

Since I'm having Buchanan's lace up new Excels, I'm thinking 19" front and 18" rear...

Pros and cons of what you chose, please?
 
I'll start by saying that I'm not a Triton guy.
But I assume that you're talking about a slimline featherbed frame. If so, I have some experience in that category. I have an Atlas special that I built several years ago, and was in your same situation when deciding on wheel sizes.

My main preference would be to run a 19" front and rear. But at the time, I opted for a 19" front and 18" rear.
I run a WM2 19 on the front with an Avon Roadrider 100/90 - 19 tire
I run a WM3 18 on the rear with an Avon Roadrider 110/90 - 18 tire
I always use those Avon tires, and I personally think they're excellent for a classic road bike.
Those 2 tires are nearly identical in overall height. Which was my goal. To have a balanced look in ride height in conjunction with the wider rear tire.

I can tell you that on a stock slimline featherbed swingarm, the clearance for the 110/90 - 18 is very tight. Once laced up (by Buchanan's), I had to adjust in order to move the rim ever so slightly towards the drive side. And even with that, the clearance is tight on both sides. About 1/16" give or take. So you spacing is important. And obviously the chain length will determine where the tire sits within the swingarm. I have some room to move my tire back which would give a bit more side to side clearance as it gets away from the taper of the swingarm towards the front. But I've settled on it's location since the drive side of the tire would have less clearance if I move it back any further. This is because I still have the welded on stock chain guard mount. So it's a bit of a compromise all around.

In the end, it's all a matter of preference I suppose. I don't think my wider rear tire selection gave me any added performance. If I were to do it all again, I'd go with WM2 19 front and rear with 100/90 - 19 Avon Rpadriders. And again, that's just preference. I like the stance of my bike to look balanced. And while it looks very balanced with the current set up, I still like the look of both 19" wheels.

Depending on your tire choice, I'd check with the maker for actual measurements. For instance, my 110 wide rear tire is listed as 116 actual width on the Avon site.
Based on the measurements, I believe that a 110/90 - 18 would fall in the swingarm at almost exactly the same spot as a 100/09 - 19. Giving the same clearance that I currently have.

All of this also depends on your shock length and also possibly your center stand. I've heard some say that with the larger tires, the bike would be unstable on the center stand. I've never had that problem, but figured I'd note it. You could always weld some thin metal pieces onto the bottom of the center stand feet if you encounter that problem.

Hope this info helps. Again, this is just my personal opinion and personal experience.
 
I too had an Atlas with a 19/18 inch wheels which I fitted with the old Dunlop TT100s of the old size 4.10 18/19inch with no problems.

Quote “I can tell you that on a stock slimline featherbed swingarm, the clearance for the 110/90 - 18 is very tight. Once laced up (by Buchanan's), I had to adjust in order to move the rim ever so slightly towards the drive side. And even with that, the clearance is tight on both sides. About 1/16" give or take. So you spacing is important. And obviously the chain length will determine where the tire sits within the swingarm. I have some room to move my tire back which would give a bit more side to side clearance as it gets away from the taper of the swingarm towards the front. But I've settled on it's location since the drive side of the tire would have less clearance if I move it back any further. This is because I still have the welded on stock chain guard mount. So it's a bit of a compromise all around.”

I once saw a Manx Norton of which the owner fitted an extra wide 18 inch racing tyre; the owner solved the swing arm clearance problem by filing out the section where the shoulder rubbed onto the tyre wall and brazing a small section of metal into the gap.
With 18 inch rear wheel you will need slightly longer shocks to raise the bike back to normal.
HTH.
 
I've also seen instances where some have notched the swingarm in order to keep the tire from rubbing. Sometimes with very heavy notches and then metal plates welded in.
Personally, I would never recommend that technique. There's not enough featherbed frames out there for that sort of heavy modification. I think the 110/90 - 18 tire is plenty wide.

I suppose that if you're building a Triton, perhaps you're not concerned with keeping the frame stock. But there are other options if you really want to run an extra wide tire. Dresda makes a boxed swingarm that will accommodate a very wide tire. And although I don't think it looks appropriate for a featherbed frame, it's an option.

Just my 2 cents.
 
I'm going with the Dunlop 501 GTs as I have on my race bike. The 18 rear is 110/90 and I like the stickyness better than the Avons.
 
19 inch wheels are best on a featherbed with the motor as far forward as possible. My mate's 650cc Triton has 18 inch wheels with the motor an inch back from where it can be. It is very pleasant and neutral handling in corners - can be ridden quick enough in corners.
When my 500cc Triton had the motor that inch further back with 19 inch wheels, it was unrideable in corners - so I moved the motor forward until the mounts touched/ The bike was much quicker than my mate's 650cc Triton in corners, but his bike was quicker on the straights. Then I reduced the wheel size to 18 inch on my 500cc Triton to get better rubber, and completely stuffed the handling. The bike was no quicker in corners, but when I got off it after racing, I was always completely stuffed.
Tyre width makes no difference with a featherbed as far as grip is concerned. Because of the steering geometry, it is usually impossible to get much lean. Friction depends on force per unit area. Triangular tyres did not do much.
 
If you watch the video 'The Right Line' there is video of Bob McIntyre on a Manx on Oulton Park. You can a see him tip the bike onto the sides of the triangulars. He died on that track. Going onto the sides of the triangular tyres is a sudden movement
 
Grandpaul canvassed for opinion by starting this thread THIRTEEN freakin’ years ago Al !

I’m gonna go out on a limb here and suggest that he may well have made a decision and had those wheels built by now…
 
Grandpaul canvassed for opinion by starting this thread THIRTEEN freakin’ years ago Al !

I’m gonna go out on a limb here and suggest that he may well have made a decision and had those wheels built by now…
Yep, 3 days after the original post, about 4 posts down.

Triton wheel size poll
 
I would not build that bike with that engine. It does not make sense to use it in a featherbed frame. Tritons were built because we could not buy Manx engines. Some Manx Nortons were available without motors, because the car guys used to buy a Manx to get the motors for 500cc car racing. A 1963 Bonneville was a very good motorcycle. The bike in the photo looks good, but the gap behind the gearbox - ? - 'Because I can' is never a good reason to do anything.
With that frame, I would use a Norton twin motor with a separate gearbox. For any sort of historic value, a Triton needs the wideline frame and a non-unit motor.
Whenever I build a motorcycle, I try to make it correct for its period. If I had that motor, I would look for an appropriate frame. The bike in the photo would make a good 650SS.
I am sorry if I have rained on your parade, but I have built about 5 motorcycles out of parts. I always think a long way ahead before I begin. The main stumbling block is usually the gearbox.
 
I would not build that bike with that engine. It does not make sense to use it in a featherbed frame. Tritons were built because we could not buy Manx engines. Some Manx Nortons were available without motors, because the car guys used to buy a Manx to get the motors for 500cc car racing. A 1963 Bonneville was a very good motorcycle. The bike in the photo looks good, but the gap behind the gearbox - ? - 'Because I can' is never a good reason to do anything.
With that frame, I would use a Norton twin motor with a separate gearbox. For any sort of historic value, a Triton needs the wideline frame and a non-unit motor.
Whenever I build a motorcycle, I try to make it correct for its period. If I had that motor, I would look for an appropriate frame. The bike in the photo would make a good 650SS.
I am sorry if I have rained on your parade, but I have built about 5 motorcycles out of parts. I always think a long way ahead before I begin. The main stumbling block is usually the gearbox.
@acotrel Please refrain from cr@p like the above on a bike that was built many years ago and has proven to be more bike than the average rider can use 100% of. Really, your nonsense is beyond the pale.

I built the bike from random parts, no working/original bikes were dismantled, destroyed, or otherwise misused, and the above nonsense was useless then, and well beyond useless now.
 
People used to believe choppers were good. I must have a different mindset. I have been building hybrid motorcycles since I was 15. It has always been about performance and handling. The Triton in that photo is similar to what one of my mates built. A few years ago, was offered a bike which was a Mk8 KTT Velocette motor and gearbox in a Featherbed frame. It had all the good parts, but it was completely wrong. In the early 1960s, BSA, AMC, Triumph and Norton - the engine and gearbox mounts were all the same width, so building hybrids was easy. The Velocette motor needed spacers to fit in the frame. But building the best motor in the best frame to get the best bike is absolute bullshit. The worst race bike would have to be the Norvin. When you ride a Triton in anger, it usually feels big and you keep bashing your knees and elbows.
If you compare that Triton in the photo with a 1963 Bonneville - ?
With that motor, I could easily win races, but not in that frame. I was involved in racing when the change occurred from Manx Nortons to two strokes. A 1963 650cc Bonneville is better than most of that time.
 
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This is a photo of my short stroke 500cc Triton after I stuffed it by fitting 18inch wheels to get better rubber. It was no faster in corners but very tiring to ride. I sold it back to my mate who had built it in about 1957 - for about $5000 - each wheel was worth that. I was extremely disappointed with what 18 inch wheels did to it.
 


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