why light wheels make your bike turn easier

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why light wheels make your bike turn easier


according to the ' press ' interviews , the ridgidity of the mags allowed P.W. to go full wellie through places
where due to the undulations flexing the spoked wheels it would weave ,unimpeded without backing off .

why light wheels make your bike turn easier


So to the Diamond Senior TT of 1967.

Friday arrived and the fickle Isle of Man weather was perfect. The tension was indescribable. The long line of starters stretched back along Glencrutchery Road towards Governor's Bridge.

Hailwood started at number four, thirty seconds later Agostini took up the chase. Agostini pulverised the lap record from a standing start breaking the 21-minute barrier with a speed of 108.38mph, to lead by 11.8 seconds.

Obviously not happy with the handling of the Honda, Mike gave a 'thumbs down' as he screamed through to start his second lap. It was not all Agostini and Hailwood. Renzo Pasolini lapped at 100.06mph from a standing start on the Benelli and the news everyone was waiting for, a British machine had gone over the ton! Peter Williams [Arter Matchless] lapped at 100.35mph.

go to 1:57 http://www.youtube.com/watch?v=c0A6BucOdK4
 
Light vintage wheels! :D

In 1967 on an Arter Matchless!

Not so academic afterall.

So Matt, how do you manage to pull together so many pictures so quickly. Are you a curator of a digital vintage library?
 
Dances with Shrapnel said:
lcrken said:
worntorn said:
These come pretty close to zero mass:

http://www.dymag.com/?q=products
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Now if they only made them in 19" sizes!

Ken
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Yes, these probably are as light as you can get with todays materials. I wonder what they would weigh in a WM3 or WM2? :) Another 30 years and it might be grapheme composite.
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I would agree with the other posters here who say lightening our Commando and other Vintage wheels can only help. But those are very heavy OE wheels and the lightweight options are not in the same league as these modern carbon fibre 2.5 kg tubeless wheels.

Again and again I read of ordinary road riders mounting these carbon fibre wheels on their road bikes and wanting to make positive comments aftef laying out $4,000 for two little wheels. Often they "think they can sense greater acceleration and braking" I believe that with 160 hp and giant disc brakes, it would be tough to feel the difference there. Basically open the throttle and you are strapped to a Rocket, whatever wheels are on there. And the stock sportbike wheels are already quite light. Mixed with the positive reports nd sometimes included in them are these reports of greater "twitchiness" or "fidgeting" at speed. The complaint is that with these feather weight wheels it is a bigger job to keep the bike going in a straight line or smooth curve, especially on uneven pavement.

Perhaps the ultra light wheels have reached a point where they are too light for comfortable everyday road use on the very imperfect roads that we ride on?
In my experience lightweight alloy wheels on vintage bikes present no such problem, they only improve things, but then, they aren't really all that light?

Glen
 
It is difficult enough to change the steering geometry on a race bike to get it to suit the riders', preferred style. I suggest changing wheel weight should be done in conjuction with the exercise of changing the rake and trail as well as tyres, and properly tested. It is easy to set a bike up in a way where it can grab you by the throat when certain situations occur. I don't think it is as simple as buying a pair of $4000 wheels and just bolting them into your bike. The wheel mass is what keeps the bike upright, and gives it feel at speed. It is the reason that bikes become more stable, the faster they go, and as the suspension pumps down . On an old classic bike the handling situation is vastly different to modern MotoGP bikes which seem to be always in a state of balanced power sliding.
 
according to the ' press ' interviews , the ridgidity of the mags allowed P.W. to go full wellie through places where due to the undulations flexing the spoked wheels it would weave ,unimpeded without backing off .
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Dances misses or confuses the point [again?] of lighter Mg wheels benefit in vintage cycles, of more stable construction rather than just less mass, though both help as the record showed. The above interview quote implies the stiffer-rigid wheels mattered most.

My testing of old vs new vintage size tires reveals similar phenomina but oppositely, the harder stiffer old tires made me back off my un-tammed Combat d/t isolastic-frame upset before traction limits showed up. If hit lumpy-gusty surprise conditions going too fast for the old tires [unintended] so was fighting with body strength to resist the Hinging the Combat would lose grip by flopping so much it lifted tires out surface traction. Maybe altering geometry might help some but I doubt it. If I lowered air to soften the stiff old tires ride they then got too unstable distorting for much fun. New tires aired up to normal ranges definitely allowed more security smoother. BTW when I say going 'too fast' on un-tammed Commando on old tires, I mean just a bit faster than completely secure as I know how dangerous real Cdo's are so always hold back enough reserves not to really have close calls crashing a Cdo - just mild frights to catch in time and re-enforce disappointment to ride very hard on a rubber baby buggy.

I had to make decision on Peel's on or off road handling priority on selecting new wheels
and realized rough road-wind conditions is more similar to off road antics and everything that made Gravel travel and pasture flights more secure paid off even more on pavement plus all off the off roaders are sticking to spoked rims, so have I. In Peel and other hi performance cornering cycles there seems to be a threshold of wheel mass that may not help any more - so just light enough [as a Mg wheel] is plenty good enough.

Tri-linked isolastic performance is outside range of others experiences and mine too prior, = Peel's pavement handling even beyond what's seen in elite racers in chicanes is so very secure stable and tame predicable - its just not that exciting so don't need nor seek anymore improvement for tarmac but pure power to mass increase, its only the off road handling I'm interested in anymore. The few race tracks I've been on and many those I see in video often have beat up pounded frost heaved rough sections, so another reason for Peel to be configured off road style rather than lean limited over stiffed road style.

Stiff lighter vs compliant heavier wheels when going gets Tough!
https://www.google.com/search?q=spoked% ... channel=np
 
When the first mag wheels appeared in Australia they had usually been copied from items from O/S. One of our guys had them cast at Commonwealth Aircraft Corporation where they had an aircraft casting facility which could cast magnesium. The original wheels were used to make the shape in the moulding sand, however nothing was allowed for shrinkage. One wheel cracked a spoke during use, and complaint was made to CAC, who refused make any more for motorcycles. The Campagnolo wheels were ace, however I thought the Dymags on my TZ350 were crude.
 
Is it still possible to buy good 18 inch forged magnesium or even aluminium wheels ?
 
acotrel said:
When the first mag wheels appeared in Australia they had usually been copied from items from O/S. One of our guys had them cast at Commonwealth Aircraft Corporation where they had an aircraft casting facility which could cast magnesium. The original wheels were used to make the shape in the moulding sand, however nothing was allowed for shrinkage. One wheel cracked a spoke during use, and complaint was made to CAC, who refused make any more for motorcycles. The Campagnolo wheels were ace, however I thought the Dymags on my TZ350 were crude.
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Re; “however nothing was allowed for shrinkage.”
Another blundering amateur’s attempt that bites the dust :!: :( :? :shock:
 
I think that technical error has been made a few times when guys have tried to copy by casting. I saw the complete front end come off a bike at one of our race meetings. One of our smart aleck's had recast a set of Honda fork yokes in aluminium where originally they were a steel forging, and took an impression off the steel forging to make the mould. Not only did he not allow for shrinkage which reduces the section he chose the wrong manufacturing technique for the wrong material. The guy responsible does a lot of work on the big Hondas which dominate one of our historic classes. The next thing that happened was that another idiot blamed a 'hole in the track', and the controlling body went looking for it - there was no hole !
Some of these experts grab the money and say 'there you go', and on at least one notable occasion it has cost a life.
 
Dances with Shrapnel said:
@acotrel

http://www.dymag.com/?q=products

Their classic CH3 line is magnesium and includes the following in 18"

18" x 3.50/4.00/4.50/5.00

No mention of whether they are cast or forged.
Click to expand...

If they are true to the originals, they are cast. Dymag didn't start forging wheels till well after this wheel design.

Ken
 
Lightness is rightness, so drives some to extremes to obtain. Here's more details on the scope of this as applies directly to vintage Commando and semi-vintage Commando-classed specials. I've rescued a fella with a can of inflate-a-flat foam to see it begin ozzing out spokes but it got him 5 mile further to a station with a phone. I have gotten my balloon tire flat fixed with a plug and some air by farmer shed. Also struggled with mulit holed tube to patch in a field, ugh.

tubeless-spoked-rim-t15074-15.html

http://www.triumphrat.net/maintenance-a ... ville.html
 
So . . . . . . . . . . is it settled?

Light wheels do make your bike turn easier AND always improve handling/roadholding.

? ? ? ? LOL
 
Absolutely agree.

.......unless they are featherweight carbon fibre jobs in which case they might cause twitchy behaviour... :lol:

Glen
 
The bike should inspire confidence. I don't like 'twitchy' or the anxiety it can create. I will never crash again (until the next time).
 
why light wheels make your bike turn easier



Ugh, the few carbon wheel tests on moderns revealing factory wheels slight advantage agrees with acetrel and my findings, poor cripple can become too twitchy-scary if not wearing its prescribed heavy corrective orthopedic shoes with a lift in one of em to get around better and not fall down. A really neutral light handling cycle will not fall down even w/o any gyroscopic effect from wheels. What does help to stay on turning slide at constant lean angle on firm or loose stuff is the crank shaft gryo so helps to be in lower gear to slow wheel spin down while keeping rpms up w/o much throttle. [after the antic to break free to do so, suddenly loads and control forces lighten up don't ya know] 1/2 sec was mentioned in the corner cripple balloon tire tests though sections of the track. I Think 1/2 sec ahead in drag race with heavier wheels as quite significant, its rather huge difference in 'chicanes' the tests most concerned. Alan my rule is never ride so it scares me, but for the life of me I could not induce that on pavement with Ms Peel, so sought out off road unpredicable traction and surface lumps and holes and washboards about crashing me to jerk a save this way or that in nick of time - time after time, to get my adrenalin weak knee tremble state I long for.
 
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