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Discussion Starter · #1 ·
There's an interesting comparison between CB450 and Royal Enfield Electra-X bikes (which I'm very familiar with). When the Electra-X was sold the UK importer fitted Avon Roadrider tyres - 90/90/19 front and 100/90/18 rear. The original Enfield fitment for the rims was 3.25/19 and 3.50/18 (same as the CB450).

One aspect of this change was a noticeable lowering of the bike. For example, the Avon 110/90/18 has an overall diameter of 642mm but an imperial Heidenau 3.50/18 has a diameter of 663mm and therefore fitting the Avon gives a 10.5mm lower height. This doesn't bother me but my Wife needs all the help she can get whilst riding the Honda. Otherwise I would pick the Heidenau K34 all day long over anything else.

Swings and roundabouts, though - that 10.5mm reduction makes getting the bike onto the centre stand a real haul.

So my question is, does anyone run 90/90/19 front and 100/90/18 rear Roadriders?
 

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Not wanting to make the speedo more off, I went with 100/90-19 front when Avon stopped selling inch-size tires here. I've always used a 4.00-18 (close to a 110/90) on the rear. But then, I've lowered the overall height of the bike by nearly 20mm. To use the center stand, I roll it up onto a 1.5" board, fitted with a ramp adapter on one end, and a 1x2 as a stop at the other, so I can roll it to the stop. The stop is set so the stand just clears the board in front. If I need the stand away from home, I usually enlist the help of someone, or roll it back fast enough to jump onto the stand. Since you're only talking 10mm, a sheet of plywood would make that up, and wouldn't need a ramp; a bit of molding at the front as a stop, and you're set.
 

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I have Roadriders on my Bomber and a K1 with 90/90-18 front and 100/90-18 rear. I haven't had any difficulties getting onto the center stand. Both bikes came with oversized (and downright petrified) tires to begin with.
 

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Discussion Starter · #4 · (Edited)
Now you mention it WintrSol, I'd forgotten about the speedo inaccuracy if a 90/90/19 front was fitted. Damn, there's always something. At least it's in the right direction to avoid a speeding ticket.
 

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I have road raiders on my 74' CB450 100/90 19 front and 100/90 18 rear. Both rims are 1.85" wide.
 

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Bombers and K1s came with 18 inch fronts. I'm not sure about K2s. The 19 inch rim came with the disc brake, I believe.
 

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Discussion Starter · #9 ·
After lots of deliberation I went with a 90/90-19 front and 100/90-18 rear. The worse case I came up with was a 4% speedo error with the replacement front tyre. As it happens it's almost identical in diameter to the part-worn original Japanese Dunlop Gold Seal that was fitted (which had to be sawn off, it was so hard). The new rear is 0.3" wider than the 4.00x18 CST that was fitted and looks good - not too skinny, not too fat. There's now a fair difference in the seat height. My wife can now get both feet flat on the ground, but it's one heck of a heave onto the centre stand so I may get another stand to modify. I'm fairly tall so have to bend over quite a bit to grab the lifting handle so it puts a lot of strain on my lower back.

I've bought quite a few Avon Tyres over the years but these came labelled up as 'Cooper Tire'. I didn't know that Avon is a USA-owned brand.
 

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Centerstand lifting.....Bend your knees and use your leg muscles, Lock your arm while back straight from the waist up.....
Straighten legs while arm guides backwards ......
 

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I only use the center stand at home, when I'm going to check something that needs the bike upright, to get it onto a lift, or to clean and oil the chain, so just roll it up onto that board. Once, I needed the center stand away from home, but was riding with friends, so one grabbed the luggage rack and lifted.
 

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Discussion Starter · #12 ·
The knees bent/back straight thing never really worked for me - I'm 6'7" with a 37" inseam and the leverage is against me, plus my bent knees push me too far away from what I'm trying to lift. A good, used centre stand is inexpensive so I'll get one to experiment with but in the meantime I'll use the board method to make life easier.
 
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