Why not shockproof oil in TTI boxes?

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Onder said:
OH ALL RIGHT...Ill have to order some up and try it out.
Perhaps it will be the only substance on earth that can enable
an Enfield Albion box to survive.
Click to expand...

It’s good stuff.

But it’s not magic...
 
I struggle to imagine that your stomping 920 will benefit from 6 gears Yves.

In fact, it might make you go slower, more gear changes means less time at WOT!

Neil Beadling, who looks after most of the top triple race motors, told me that many of his riders of big triple motors prefer the 5 speed, as the 6 speed means more gear changes and slower lap times.

I also deliberated getting the unpolished TTI gearbox outer cover polished, but I hit it with the wire brush and scotchbrite pads and it looks great IMHO, especially with my quest for a slightly de-blinged overall look.
 
yves norton seeley said:
..........
If I can save the money, I plan to buy a 6 speed TTI this winter
Yves
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My 750 short stroke works fine with a 5 speed, even if originally I wanted a 6 speed...not for the extra gear at one circuit, but to be able to select one overall final drive ratio and have no need to change gearing for each track. First for starts, but after that, top 5 at one track, bottom 5 at another!

But really with your 920 I cannot see the use for a 6 speed, road or track. And I should admit that even with 5 I sometimes lose count!
 
SteveA said:
even with 5 I sometimes lose count!
Click to expand...

Why not shockproof oil in TTI boxes?
 
I had friends who told me that because I had a torquey motor, I did not need a close ratio box. They had probably never used a close box with a torquey motor. The acceleration rate is much faster because you ride the top of the torque curve. With 6 speeds, close ratio - you are never short of a gear when you need it, but even 5 is good.
 
oldbeezer said:
You may want to get your eyes checked:), it is a Suzuki but 14! speed. The bike is a 60s twin cylinder 50cc 2 stroke GP bike.
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No not my eyes, I didn't count the gear wheels, I was working from memory :( I think they started with a mere 10 on earlier bikes before they hit the silly speeds! And all part of the reason that GP machines were later restricted to 6 speeds......
 
acotrel said:
I had friends who told me that because I had a torquey motor, I did not need a close ratio box. They had probably never used a close box with a torquey motor. The acceleration rate is much faster because you ride the top of the torque curve. With 6 speeds, close ratio - you are never short of a gear when you need it, but even 5 is good.
Click to expand...
A good close ratio gearbox needs to be able to keep the engine in its ideal powerband at any given instance on the track (or road) in question.
That is irrespective of whether the powerband is high up, or low down in the rpm range.
Most people assume a ‘torquey’ motor will have low down grunt AND still rev out and thus have a wide power band. But it’s not necessarily so.
But surely even a tuned Norton has a powerband of around 2000rpm at least?
I still find it hard to imagine many (any) instances whereby a 6 speed box is better in a Norton than a well designed 5 speed.
Some of those Japanese two strokes (and Honda four strokes) had such incredibly narrow power bands, the engines were virtually on / off switches and any acceleration or deceleration required gear changes.
If racing is to ‘improve the breed’ and trickle down to road bikes, that design route was clearly flawed, hence, I believe, limiting gearboxes to 6 speeds was a very sensible move as it forced engine designers to focus on wider power bands.
 
If the objective is to go faster, then a narrow, high output power band and a big number of close ratio gears is the way to go. If racing is to more involve rider ability, 6 speeds close ratio is probably enough. Because you have a torquey motor, that doesn't stop you from getting advantage by riding the bike as though it is a two-stroke. If you have the correct gear for every situation in a race - would that help ? What people forget is that there are two parts to every race circuit - the fast bits and the slow bits. If you haven't got the legs on the fast bits, you need more on the slow bits. I don't worry too much if I get passed towards the ends of the straights - the next corner is usually too difficult for them. But if you get passed halfway down the straights, you have a problem.
 
The easiest bike I have raced was the methanol-fuelled T250 Suzuki I built. It had the standard 6 speed box with the low first gear. It was extremely direct steering and very nimble. I ride my Seeley the same way. With TZ Yamahas, most have close ratio boxes with a higher first gear. The RD400 has the same ratios as the TZ350.

Why not shockproof oil in TTI boxes?
 
Last edited:
Hi

Many years ago I spoke to Phil Godfrey at Silverstone, they had fitted a 6 speed to the
P & M 750 trident. The 2 Phil's ( Phil Davenport the rider) were at the top of their game & said they needed it to compete. What surprised them was the 930 big bore engine, they didn't think it needed it. At Silverstone it was a second a lap quicker!
I have a 5 speed on my 960, I wouldn't update to a 6 speed but if I was starting from scratch?

Chris
 
I still have not had the opportunity to play with my 6 speeder yet, however I should have one on 6th October this year. When I ordered it, I asked Bruce to place first gear halfway between a Commando and Manx. He said 'I know what you mean'. If you have first gear fairly low and the rest close together and higher, when you increase the overall gearing, you only significantly lose revs on the change between first and second - which usually occurs around the first corner in a race. So you rev the tits off the motor. After you are out of first, you usually never go back to it. The more gears you have in the close group, the better you can cope with a rise in the overall gearing - so you become faster towards the ends of the straights and are still quick coming up through each gear. A lot of guys don't know how to race-change up through the box. Once I am in second in a 5 speed or 6 speed box, I race change by slightly easing the throttle and pressing gently down on the change lever. I don't use the clutch. There is probably a mismatch of 200 RPM, but the box will cope with that. It becomes like playing a musical instrument as you move up and down through the gears. It is extremely easy to over-rev as you come up through a close box. With a Commando engine, once you lose revs, it is all over - slow ! If you wait for it to spin up again on the throttle while pulling, you will wait forever.
If I find that I can raise the overall gearing because of the close group of five gears, I might have to buy a lower first gear for clutch-start races, and live with the gap between first and second.
 
Chris, Lee Gourley was one who either didn’t want a 6 speed or had it removed and re-fitted a 5 speed (can’t remmeber which) and he was pretty much at the top of the league at the time (not sure what he’s up to now days though?).
 
Chris, thanks for your comment. It does not surprise me. Most of us have never been able to afford trick gearboxes. Unless we have experienced using one, we probably don't know the difference. The standard Commando box might be OK in a road bike, but I tried using one in a race. I couldn't do anything with it - up or down, it was useless. Four speeds close ratio is OK, but they were designed for push starts. For clutch starts, you need that low first gear. The gear spacing of the higher close group often determines how high you can raise the overall gearing. In a 6 speed box, the gear spacing is closer than in a 5 speed.
 
If you have got a lazy brain, 5 speeds are easier to cope with than 6. R5 Yamahas had 5, RDs had 6 - we soon got used to them. I used to count gears as I rode, but these days I only ride on a circuit with which I am very familiar, so I always know what gear I am in. As I approach the corners, I know what the motor should sound like and what the corner should look like.. I think some R5 Yamahas had 6 gears with the 6th gear locked out, until the motor was operated on.
 
Hi Nige

lee had a bad one at the Ulster. Rehab, retired from racing, this was a fair few years ago. Although he may? have raced this year, although I dont know the specifics, just a coment off Ken on the CRMC site.
Lee was the man, I have one of his North fairings (purple & yellow) built like a brick shithouse lol. I slid down the track on oil in the rain at Cadwell at 30mph & wore through the casing on a triple. Fairings are a practicle thing. His sponsor in 501 unlimited was a lovely man but I dont know the engine spec. I believe crank weight has a great effect on feel & how hard you can push a bike. 5 gear or 6 then comes into the equation.

Chris
 
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