19 Vs 18 Wheels (2015)

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jaguar said:
I need to changed the wheels on my 850 Commando due to rust.
Got me thinking about swapping to alloy hoops.

Should I get 19s front and rear? 19 front 18 rear? 18s front and rear?

Looking for a more performance oriented set up.
Open to any and all advice.

Thanks
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Are you looking for performance on street or racetrack? Frankly the original rims with AM26 100/90-19 both ends have not disappointed or failed me on the street. I’ve slowed down now, but was part of the “fast crowd” in the 80s onward on NCNOC club rides.
 
Most motorcycles understeer, so tend to run wide in corners as you accelerate around them. When I changed the wheels from 19s to 18s on my Triton, I got better rubber but the bike became more difficult to turn. I was extremely disappointed, but the way back was too expensive. With a road bike it might not matter too much, but with my racer I used to get off the bike buggered after a 3 lap race on a short circuit. I could ride the bike faster in corners, but with much more effort in keeping it away from the outer edge of the bitumen.
With a Commando, it might matter how aggressive the correction was, that was made to change Peter Williams' specification for the first Commandos. The first Commando might have been the best, but was changed to suit the average punter.
In effect, with a later Commando you are probably one step away from the best handling and reducing the wheel size might take you one more step further away, by reducing the trail.
 
Thank you all for your input. I think we have decided to stay with 19s as originally planned and go with WM2 front and WM3 rear.
 
mwedd said:
Thank you all for your input. I think we have decided to stay with 19s as originally planned and go with WM2 front and WM3 rear.
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Have a rethink. Why would you think that two different rim thicknesses would work well with the same tyre?
 
Fullauto said:
Have a rethink. Why would you think that two different rim thicknesses would work well with the same tyre?
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Well the front tyre and the rear tyre have different functions, one steers and brakes, the other provides drive. A narrower front gives quicker steering and a wider rear gives more contact for the drive. The original Earles Court Commando had a 19 WM2 front and an 18 WM3 rear which was standard for the time for T120 and other high performance bikes.
 
Re;18in rear. In general 18 in road tyres have the same rolling circumference as a 19 (more or less) so, you have a much wider choice of tyres for 18 rims than 19.
 
I can tell you that a 100/90 Avon Roadrider on 2.5 inch rims at both ends gives better stability and quicker steering than anything else I've tried. If you don't believe me, try it.
 
Fullauto said:
I can tell you that a 100/90 Avon Roadrider on 2.5 inch rims at both ends gives better stability and quicker steering than anything else I've tried. If you don't believe me, try it.
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I really appreciate and value your feedback on rim choice and would like to see a couple pics showing the tire profile, I believe proper profile is the key for any tire to work properly.

I am helping my girlfriend restore this bike, it was her dad's favorite bike he had ever owned. He is living with Parkinson's and will never be able to ride it again. He has no idea she found it and bought it back and will be very surprised when he sees it again. This is part of the reason we want to keep it very original though this bike will be ridden and me being performance minded, I don't really want her riding around on the stock "pizza cutters". We want to stay with chrome steel rims to keep the stock look so that is why I had asked about the quality of Central Wheel hoops, Central Wheel seems to be one of few companies who rolls steel rims in WM3 an WM4 widths. I have purchased plenty of Excel rims from Buchanan and laced them up for flat track bikes but have never purchased Central Wheel, are they a quality product?

Thank you and I hope everyone is staying healthy through all this crap in the world today!
 
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Buchanan sells chromed Excel rims. It'd be hard to tell them from steel.
 
maylar said:
Buchanan sells chromed Excel rims. It'd be hard to tell them from steel.
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Thanks Dave, I was aware of that, I think they're in the neighborhood of $55-60 more per for chrome. Maybe it's time for me to become a dealer..
 
You might be kidding yourself, if you believe fatter tyres give more grip. What they really do is handle heat better on very high performance bikes. With a Commando, you only have 60 BHP to put on the ground. Skinny tyres make the bike more nimble. The friction component is affected by the tyre compound, the weight of the bike and the area through which the weight is applied, as well as the heat in the tyre. A fatter tyre puts the same weight through a larger area, so there is no net gain in friction. A skinny tyre comes up to temperature quicker.
I was reading an article about the Mead and Tompkinson BSA B50 endurance racers. They got faster lap times when they went from 18 inch to 19 inch wheels. The reason probably has to do with the way the bike steers. Larger front wheels increase the trail and can improve the way you can put the power on when coming out of corners.

I use a fat tyre on the back of my Seeley 850, mainly because it wheel-spins when coming out of some corners - which makes the tyre get hotter. If it gets too hot, it would lose more grip. Because the tyre is fat, the heat is handled better. With a road-going Commando, you would never get there.
 
mwedd said:
Thanks Dave, I was aware of that, I think they're in the neighborhood of $55-60 more per for chrome. Maybe it's time for me to become a dealer..
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If you are riding frequently in rain or mist, or the air is moist, forget aluminum or chromed steel. There is just one lasting alternative - stainless steel. Not as bright as chromed steel though, but while chrome deteriorates, stainless steel can always be polished to as new condition.

Chromed aluminum is for indoor use. I've seen lots of examples where chrome starts to flake off aluminum parts exposed to the elements and the looks is appalling.

-Knut
 
mwedd said:
I really appreciate and value your feedback on rim choice and would like to see a couple pics showing the tire profile, I believe proper profile is the key for any tire to work properly.

I am helping my girlfriend restore this bike, it was her dad's favorite bike he had ever owned. He is living with Parkinson's and will never be able to ride it again. He has no idea she found it and bought it back and will be very surprised when he sees it again. This is part of the reason we want to keep it very original though this bike will be ridden and me being performance minded, I don't really want her riding around on the stock "pizza cutters". We want to stay with chrome steel rims to keep the stock look so that is why I had asked about the quality of Central Wheel hoops, Central Wheel seems to be one of few companies who rolls steel rims in WM3 an WM4 widths. I have purchased plenty of Excel rims from Buchanan and laced them up for flat track bikes but have never purchased Central Wheel, are they a quality product?

Thank you and I hope everyone is staying healthy through all this crap in the world today!
Click to expand...

I'll take a picture or two today for you.
 
acotrel said:
You might be kidding yourself, if you believe fatter tyres give more grip. What they really do is handle heat better on very high performance bikes. With a Commando, you only have 60 BHP to put on the ground. Skinny tyres make the bike more nimble. The friction component is affected by the tyre compound, the weight of the bike and the area through which the weight is applied, as well as the heat in the tyre. A fatter tyre puts the same weight through a larger area, so there is no net gain in friction. A skinny tyre comes up to temperature quicker.
I was reading an article about the Mead and Tompkinson BSA B50 endurance racers. They got faster lap times when they went from 18 inch to 19 inch wheels. The reason probably has to do with the way the bike steers. Larger front wheels increase the trail and can improve the way you can put the power on when coming out of corners.

I use a fat tyre on the back of my Seeley 850, mainly because it wheel-spins when coming out of some corners - which makes the tyre get hotter. If it gets too hot, it would lose more grip. Because the tyre is fat, the heat is handled better. With a road-going Commando, you would never get there.
Click to expand...

He's not going to use fatter tyres, just wider rims.
 
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mwedd said:
I really appreciate and value your feedback on rim choice and would like to see a couple pics showing the tire profile, I believe proper profile is the key for any tire to work properly.

I am helping my girlfriend restore this bike, it was her dad's favorite bike he had ever owned. He is living with Parkinson's and will never be able to ride it again. He has no idea she found it and bought it back and will be very surprised when he sees it again... Thank you and I hope everyone is staying healthy through all this crap in the world today!
Click to expand...


That is a very Cool and Noble gesture Sir.
Please keep us in the loop and show the final bike.
Looking forward to this.
 
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Don't worry about the dirt, I wash it every nine months whether it needs it or not.
 

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Fullauto said:
I can tell you that a 100/90 Avon Roadrider on 2.5 inch rims at both ends gives better stability and quicker steering than anything else I've tried. If you don't believe me, try it.
Click to expand...
I've been running this setup now for many years and will affirm and back up Ken on this tire/rim combo.
Cheers.
T
 
WM3...WM4...18"...19'... there are a whole bunch of other things that will make a bigger difference to your handling than these rim sizes with the same tires.
 
gortnipper said:
WM3...WM4...18"...19'... there are a whole bunch of other things that will make a bigger difference to your handling than these rim sizes with the same tires.
Click to expand...

Try it. You will become a believer. Tell me how not using a rim width suitable for the tyre is not a good thing>
 
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