New video racing my 750 Commando in Superbike class at Mosport 2018

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I've got to watch this almost every day. Good run there, and pleasing to see the Honda get dusted at the end. Sharp driving and nice Snortin' Nort'.
 
acotrel said:
With that 5 speed Triumph cluster, before he died, Phil Pick used to sell two pairs of gears which moved 2nd and 3rd closer together and more towards 4th. Fast Eddie said Tony Hayward might now sell them. Closer ratios improve acceleration, even when the overall gearing is higher - might fix your down-shifting issues. I once tried racing with a standard commando box - it was appalling - slow everywhere. Even the American 4 speed close box is brilliant everywhere, except off the start. What find is that most guys always slow down too much for turn one - I go round it at the same speed I would on any other lap. So the high first gear is not such a big problem.
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Phil Pick is dead? It’s the first I’ve heard of that Al! Are you sure and what’s your source?
 
Acotrel

Please check your facts.
Phil Pick is alive & well. Although he no longer seems to be online & has not run his spares business for a number of years.
Miss his input on triples.
Chris
 
Thanks for confirming that Chris. Good to know, Phil is one of ‘the good guys’ !
 
Doug MacRae said:
At the lap times I am doing at Mosport, my average speed is 89 mph in a lap. I always feel watching the laps on video is that the end of the back straight when I go into the T8 right hander it does not look like I am going fast even though I am not touching the brakes at 130 mph and just pitching the bike into the corner, scrubbing off the speed that way and then carrying the speed through 9 and 10 onto the front straight, not much on the gas but carrying the speed. I am not sure I can go through there any faster than I was in the video, the front was starting to pogo and chatter on me
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You mention ft end pogo and chatter. What kind of fork are you using?
 
I thought I read somewhere that Phil Pick had passed away. Those two pairs of gears for the Triumph 5 speed box are an excellent idea. If 2nd and 3rd are closer and higher, the step between 1st and 2nd is bigger, but that only matters as you approach the first corner on most race circuits. The first corner is not usually very far from the start line. Top gear would effectively be an overdrive. But the middle three gears of the 5-speed box would become extremely effective. When the needle of the tach does not drop much when you change gears, you don't have to wait while the motor spins up again. It would still lag a bit when you change into top, but when you race, you don't usually get into top that often that it would matter.
 
If you read the latest Motorcycle Classics magazine, there is an article about the RD400 Yamaha. It mentions the beneficial effect of the revised gearbox. The RD350 box had wider ratios and a lower first gear. The RD400 has the same ratios as the TZ350. When you road race any road bike, you always have two problems which hold you back - the gearbox and the steering geometry. They are intended to promote safe commuting. A Commando with the standard box is as slow as a wet week.
 
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jseng1 said:
You mention ft end pogo and chatter. What kind of fork are you using?
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Using 35mm Suzuki Water Buffalo forks with emulators. They work very well but to do low 39's at Mosport on a bike that is not a high hp machine you are pushing hard through the corners and I was prob getting close the limit of what they could do. Corners 2, 4 and 8 are 100-110 mph. The Honda CR750 in the video has done 1:38 laps but has between 90-95 hp.

sportsroof said:
As always, engrossing and excellent!
Martin
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Thanks a lot Martin!
 
Doug MacRae said:
Using 35mm Suzuki Water Buffalo forks with emulators. They work very well but to do low 39's at Mosport on a bike that is not a high hp machine you are pushing hard through the corners and I was prob getting close the limit of what they could do. Corners 2, 4 and 8 are 100-110 mph. The Honda CR750 in the video has done 1:38 laps but has between 90-95 hp.


Thanks a lot Martin!
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You should be able to push your bike hard enough to drift without having suspension problems. I had to tune in my suspension to get it to work right and then I could push it all the way to where the tires began to break loose. There was a little chittering when this happened at 130+mph? (turn 8 at Willow Springs) but it was minimal and I think it went along with the tires losing traction or high spots on the track.

You also have to be sure the rear isn't chattering and transferring that motion to the front. This happened on one of Ron Woods Rotax singles that I tested for him. The rear shock had teething problems and chattered so badly that the front end went along with it. Its not easy to turn around and look at the rear wheel when you're pushing it to the edge.
 
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I had that problem with my Triton. It felt as though the front was jumping, but a friend of mine was watching and saw it was the rear end. We upped the damping on the rear shocks and the problem disappeared. But one of the main problems with bikes in corners is when you are forced to back off halfway through - the bike then tends to wallow and you go slower. If your steering is set up in a certain way so that the bike tightens it's line substantially if you gas it when cranked over, you find you don't ever need to back-off in corners and the bike tends to lean less anyway. The worst thing is if you get into a high speed bend too quickly and are going to crash either way - brake or accelerate. If the bike is right, when you turn it on again, it will go around
 
The friend who spotted the rear end of my bike jumping was an excellent A-grade road racer on Manx Nortons. One day he came to Winton with Mick Hone and Robbie Phillis and got onto Robbie Phillis's Katana. He got into the sweeper too fast and found himself in that situation - whatever he did, he was going to crash. So he turned it on a bit harder and got around - more arse than class. If the bike had not been right, he was gone. Road bike steering is not always the best. Back when I raced regularly, I simply adjusted to the bike and crashed a lot. Later I made the bike do what I wanted it to do - so these days when I ride, I ride without thinking.
 
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