Molnar Precision Ltd TGA Commando Parts

Once again Al
8 valve Rickman kit on a Triumph 650 makes little difference?
You really need to read some old race reports. It was the go to hop up kit to keep the Triumph 650 competitive against other manufacturers with bigger engines & eventually the Tridents, another bike you also dismiss. So little insight, so little fact thrown in to every discussion. Ray Night wrote a wonderful article about racing a very early standard T150 at Thruxton, have a look at the bikes he was competing against.
I've got the arse!
 
Chris said:
Once again Al
8 valve Rickman kit on a Triumph 650 makes little difference?
You really need to read some old race reports. It was the go to hop up kit to keep the Triumph 650 competitive against other manufacturers with bigger engines & eventually the Tridents, another bike you also dismiss. So little insight, so little fact thrown in to every discussion. Ray Night wrote a wonderful article about racing a very early standard T150 at Thruxton, have a look at the bikes he was competing against.
I've got the arse!
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Chris, do you have a link to this Ray Knight article?
 
When Rod Tingate was in the UK, he worked for Colin Seeley and was helping Kim Newcombe when he was killed at Siverstone. Rod was a competitive A-grade rider in Australia. One of his Rickman Triumphs had the 8 valve head. He said it did not make much difference. A lot of guys used to make 650 Triumphs rev high - they are better when they are made to pull.
I suggest it pretty much does not matter what a motor is, it can usually be made to perform as well as any other of similar capacity. The difference is in the way the power is delivered. I do not think a twin cylinder Paton 500 can ever be as good as a three cylinder MV 500. Peaky is not good.
 
My mate's 650 Triton is faster than my short stroked 500 Triton was when I had it. I rode his bike - it is neutral handling and has loads of torque. My 500 Triton was much faster around corners, but I always had to be 110% on top of it. Once I entered a corner, I was fully committed - I could not back off. My brother and another friend rode my Triton 500 - the could not get it to go around corners. It's shortcoming was it needed 6 gears close ratio instead of 4 gears close ratio. I did not usually lower the gearing.
 
It’s well accepted today that the Triumph hemi head design has limitations.

Conversely, the Rickman 4 valve combustion chamber is basically the same as modern designs.

So to say there’s no benefit is plain daft.

Having two inlet valves and ports per pot also has huge advantages over single big valves / ports because they can get a level of flow AND velocity that’s not possible in a single port / valve.

There are actually lots of benefits.

However, their downside is that some people thought they were a simple bolt on kit. Therefore many were indeed poorly built / tuned and a poorly built 8 valver will definitely be worse that a finely tuned 4 valver.

But if you compare a finely tuned 8 valve to a 4 valve, it’s way better. It can’t be otherwise. Physics dictates!
 
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acotrel said:
My mate's 650 Triton is faster than my short stroked 500 Triton was when I had it. I rode his bike - it is neutral handling and has loads of torque. My 500 Triton was much faster around corners, but I always had to be 110% on top of it. Once I entered a corner, I was fully committed - I could not back off. My brother and another friend rode my Triton 500 - the could not get it to go around corners. It's shortcoming was it needed 6 gears close ratio instead of 4 gears close ratio. I did not usually lower the gearing.
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The older I get, the faster I was! 🤣 🤣
 
Let me stir the pot a bit - as a lad I had a Yamaha DT 1 - two stroke 250 cc single .
So since they are the same displacement I suppose it could be made to perform as well as Honda’s RC 166 … LOL
 
There are two different concepts involved. A Commando motor is very unusual. It is a step further than any Triumph 650, or Royal Enfield 750. I never believed it could be made to become effective. So my Seeley 850 sat unraced for a very long time after I had built it. Most modern bikes are multicylinder and high revving, not slow revving and torquey. 4 valve cylinder heads have lighter valves and so the motor can be revved higher to give more horsepower. Light valves in a Commando cylinder head won't let it rev higher - the bottom end is the limiting factor. The effect gearing has with the Commando motor is unusual. Close ratios with very high gearing gives better acceleration.
I might be a weird rider, but when I tried to race the bike with standard ratio gears, I could not do anything with it - it was horrible. It went nowhere fast.
The Commando 850 motor is absurd - its design should not work.
The way the motorcycle handles needs to be different - what I did with the Seeley 850, the last time I raced - I could not do with a modern motorcycle.
 
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acotrel said:
There are two different concepts involved. A Commando motor is very unusual. It is a step further than any Triumph 650, or Royal Enfield 750. I never believed it could be made to become effective. So my Seeley 850 sat unraced for a very long time after I had built it. Most modern bikes are multicylinder and high revving, not slow revving and torquey. 4 valve cylinder heads have lighter valves and so the motor can be revved higher to give more horsepower. Light valves in a Commando cylinder head won't let it rev higher - the bottom end is the limiting factor. The effect gearing has with the Commando motor is unusual. Close ratios with very high gearing gives better acceleration.
I might be a weird rider, but when I tried to race the bike with standard ratio gears, I could not do anything with it - it was horrible. It went nowhere fast.
The Commando 850 motor is absurd - its design should not work.
The way the motorcycle handles needs to be different - what I did with the Seeley 850, the last time I raced - I could not do with a modern motorcycle.
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Any highly tuned Commando finds limitations with the bottom end, hence the arrival of Maney and Molnar goodies. So in that regard you are correct that putting an 8 valve head on a Commando, and getting the best out of it, would require replacement of much of the bottom end.

But that is a very different argument to saying that 8 valve heads don’t work !!
 
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The biggest fault here is Al is not looking at the machines in period. As each development came along, as each new model came along. Hindsight is a wonderful thing & all the good stuff we have now is due to development in period. But how good anything was? You have to look at results! A clubman on a 650 Triumph, quickly moved the standard frame on & the 8 valve 686 kit entered the fray. Bigger & bigger engines, after all it was 501 unlimited.
I've said enough & I'm going to take a step back lol I feel like I've been on the magic roundabout!

As an aside what a great kids programme, imagine today's programmes having a stoned rabbit "Dylan" in it.
 
Al is living in the past, how long ago did he build his Seeley and his motor is all stock by his own words except for the plug in his crank that in his own words give it a balance factor of 72%, don't know how he worked that out, but what was around back in the 70s there wasn't too much high performance stuff around and Hepilite pistons where pretty good then you could do a very minim final hone to bore clearance with them, but now there are so many new upgrades that made for our old bikes and more power without over revving them to perform so much better without the ricks of going bang and good on the people who have gone out of their way to make better performance stuff, I just wish I had the money to do some of these new performance upgrades, but then I built my 850 motor back in the 80s and its still reliable to this day with what I had back then.
acotrel said:
You have probably never raced against an old rider on a reasonable motorcycle.
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I don't know as I still ride with my mates I grew up with and we are all getting old, but we still race each other to that next twisties up in the ranges and we all ride reasonable bikes, we haven't slowed down yet where we ride, more fun than racing on a track any day as we all know our riding habits and always pushing our limits, at lease we are all still riding together.
Al it might be a bit late for you but you should have ridden a modern bike (prob would scare the crap out of you they are so good), but then you don't ride on the road, my old Norton built for handling, lightness and performance is a great fun bike with lots of improvements, but my 2016 1200 Thruxton is better and the newer ones are even better than it, but then I love both my road going bikes.

Ashley
 
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