Late model pork chop to engine brace

[Guest ratchethack]

The large tired bike will need a much tighter lean angle than a small tired to drive the same cornering speed. so you need more cornering clearance to drive a mdern bike as fast as an ancient oneat the same power level.

Somehow I'd missed this point first time around! Well taken.

 

Thanks for offering such intelligence and irrefutable logic in the fickle face of folly, Ernst.

 

I hadn't missed these points first pass, but they're so strong that I b'lieve they bear repeating:

With the fraction of engine power of an ancient bike the lower tire friction will outweigh the better handling capabilitys of a todays chassis. An ancient racing bike is optimised to make the best of the given combination engine/chassis. Underpowering a chassis with large sticky tires means you cannot apply the driving style it is made for.

So it's not unreasonable to suggest then, that Hailwood's speed through a given corner with the RC-166 250 six may've been on a par with, or even better than Rossi's capable of today with state-of-the-art open-class gear??

 

Ernst, (or anyone else), this is important. please respond ASAP. Need fresh fuel for "inspired" bar talk this evening.

[dlaing]

Somehow I'd missed this point first time around!

I had missed it too. A good point, but is it 'much tighter' or a 'little tighter'? How much tighter?

How does it compare to the how a fat tire allows a greater lean angle before parts grind?

IF a wider tire only allows 'slightly more' bike lean angle before bits touch, and a wider tire requires 'much tighter' lean angle, then for the same speed, a wider tire will grind more bits at the same speed!!! Tell me it is not true!!! At the very least, the wide tire is putting the suspension at a worse lean angle if the rider does not lean out further. But is speed actually reduced at the grinding bits bike lean angle???????????????

If so, how can I switch to a 120 rear tire? Alpina rear hub with Alpina front rim??? Who is going to be the first kid on the block to do what everyone appears to agree is the right thing to do? Guaro? Possibly too much power??? Ratchet?

If you have 120 front and rear, you could even carry a spare tire!!!!!

But you might lose out on the BOGO free deals.

[macguzzi]

For anyone interested http://www.tonyfoale.com/

[macguzzi]

more

[Guest ratchethack]

I was just looking at an old partially disasembled IT 250 frame. It's a big spine with monoshock routed down the center of the huge spine tube. It's more alike Foale's frame than not. Same with its swingarm. I wonder who it inspired?

Hmmmm.

 

Who was zoomin' who??

 

Egli TZ250 frame

[motoguzznix]

So it's not unreasonable to suggest then, that Hailwood's speed through a given corner with the RC-166 250 six may've been on a par with, or even better than Rossi's capable of today with state-of-the-art open-class gear??

 

Ernst, (or anyone else), this is important. please respond ASAP. Need fresh fuel for "inspired" bar talk this evening.

Ratchet

 

The only figure that influences the possible steady cornering speed of any 2 wheeled vehicle is the friction between road and tire. Theoretically.

This friction figure determines the centrifugal forces that can be applied to the tire. The centrifugal force is determined by the cornering speed and the vehicle weight. The resulting vector shows the lean angle necessary for the given speed. Every other figure like tire width or wheel diameter do not influence the formula.

There might be some person with better english capabilitys to explain this.

 

So - has the friction figure road to tire raised since the days of Mike the bike?

Maybe a bit.

If a todays bike allows the lean angle necessary to reach the cornering speed of a historic small tired race bike, it could also do slightly better. If you applied the same sticky rubber compund to the small tire, the match would be on a par. But the small tire with that soft rubber would not last very long.

[Guest june]

I'm sorry i cant answer the question.If somebody do,i'll join in.

[Guest ratchethack]

If a todays bike allows the lean angle necessary to reach the cornering speed of a historic small tired race bike, it could also do slightly better. If you applied the same sticky rubber compund to the small tire, the match would be on a par. But the small tire with that soft rubber would not last very long.

Please forgive. I'm nothing close to a racing type, and I don't fully comprehend such things. Yes, I know I'm obsessing. . .

 

Roger the trade-off between durability and grip. Things have without question improved immeasurably in this department in 40 years, the improvement being on the durability scale, not so much (if any, it would seem) with grip!

 

Wot I'm driving at now is the heretofore not fully grasped idea (at least by Yours Truly) again -- that Hailwood's speed through a given corner with the RC-166 250 six may've been even better than Rossi's capable of today -- even though Mike without much question suffered with relatively short tire life, and was forced to do tire changes that Rossi isn't encumbered with. . .

 

As you point out, Ernst, the grip, or friction attainable between track and tire is the only true measure of the limit of speed through a corner. But since Hailwood's RC-166 250 six was undoubtedly quite a bit LIGHTER than Rossi's factory rides today (how much lighter, I haven't the foggiest?), but it undoubtedly generated less centrifugal force. So with the relative advantages over Rossi of a more EFFECTIVE lean angle, AND lower weight (power and torque being no determining factors WRT speed through a corner), Hailwood may well have been able to best Rossi thru a given curve??

 

C'est possible, mais non?

[Greg Field]

Imagine if Hailwood had "hung off." That would be comparable, or if Rossi were sitting up in his seat like Hailwood is. I would very surprised if Hailwood's cornering speeds're higher. This is not because I believe Rossi the better rider. Actually, I think the opposite is more true.

[Guest ratchethack]

Imagine if Hailwood had "hung off." That would be comparable, or if Rossi were sitting up in his seat like Hailwood is. I would very surprised if Hailwood's cornering speeds're higher. This is not because I believe Rossi the better rider. Actually, I think the opposite is more true.

Seems to me that Hailwood didn't "hang off" because there was no advantage of doing it with state-of-the-sport machines of the day, since ground clearance wasn't a limiting factor relative to grip of the tires.

 

Bear with me here. . . Taking this thinking the next step, as both machinery and tires evolved, and tires ballooned up to cope with the necessity of handling BIG POWER and TORQUE so that riders could take full advantage of great whalloping hard drives out of corners and raw acceleration without instantly shredding their tires, they gave up what was relatively minor effects on lap times formerly consisting of higher speed thru corners in a trade-off. Grounding hard parts then became the limitation of speed thru corners, along with improved grip of tire compounds, and therefore hanging-off became a necessity to realize optimal speed thru corners. Err, make any sense?

 

Just my take. Somebody stick a hot poker in this, if I'm off base. . .

[Guest drknow]

Imagine if Hailwood had "hung off." That would be comparable, or if Rossi were sitting up in his seat like Hailwood is. I would very surprised if Hailwood's cornering speeds're higher. This is not because I believe Rossi the better rider. Actually, I think the opposite is more true.

 

Corner speed has increased. The tires have so much more grip it isn't even comparable. Look at 125 GP bikes. In the last 10 years, almost nothing has changed with regard to horsepower or weight. The lap times have plummeted due to the increase in tire performance.

 

The change in horsepower on bikes has led to a different riding style, so while some modern techniques enhance corner speed (hanging off, etc), squaring up corners and using the huge horsepower available now has certainly decreased mid-corner speed in some kinds of corners. There's not a lot to really argue about here. Ask any vintage racer that uses his bike in a class that requires bias tires, and another where he can use modern rubber. There is so much more grip, that sometimes the bikes don't even work with the new rubber, as the forces generated in the chassis render it practically inoperable! IF they have a chassis that can handle the additional forces, they go faster.

 

dk

[Baldini]

Seems to me that Hailwood didn't "hang off" because there was no advantage of doing it with state-of-the-sport machines of the day, since ground clearance wasn't a limiting factor relative to grip of the tires...

 

Wether ground clearance or grip was limiting factor to lean, hanging off would have decreased lean angle at a given corner speed. At full lean, before acceleration, hanging off is only really necessary when all clearance &/or grip is at limit.

 

 

...different riding style...squaring up corners and using the huge horsepower available....There's not a lot to really argue about here...

 

Saying Rossi is faster than Hailwood or vice versa is a nonsense. Different eras, different stuff, but what stays the same is they are/were both racers through & through. Rossi knows how good Hailwood was & respects that, as would Hailwood have recognised Rossi. Same for any other of the great racers, look at Moss & Fangio. They know & knew, anyone who really understands their art will recognise the same in others.

 

KB

[Guest ratchethack]

Saying Rossi is faster than Hailwood or vice versa is a nonsense.

Indeed.

 

I'm still wrestling a bit with something completely different here, that being the racing tackle -- not the riders.

 

I'm trying to figure out if ultimate speed through a corner (assuming Hailwood and Rossi were each capable of demonstrating the ultimate capabilities of racing machines of each era) has actually improved, stayed the same, or even -- dare I suggest such blasphemy?! -- decreased over the years in deference to optimizing racing tires for wot they without any question do best TODAY, that of course being immeasurably better at working with today's power and torque, chassis and suspension, etc. to deliver vastly superior lap times. Today's racing tires, relatively speaking now, are (again without much question), developed more in the direction of optimizing acceleration capabilities, and no longer so oriented as they once were by performance trade-offs in the direction of optimizing speed thru corners.

 

I think of it this way: For most tracks TODAY, all else being equal, which tire will be chosen to get round in less time -- the one with an ability to get that power and torque to the tarmac quicker out of bends with less wheelspin and quicker up to max speed and back down again for the next bend, or the tire that gets you quicker through the bends? I reckon it's the former, but that's just me.