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You don't really want a rear tire on the front. They are designed differently. A rear tire is designed to with stand both braking and acceleration forces. A front just braking.
Some say running a rear on the front is ok if you reverse the direction of rotation arrow.
Doesn't Avon make front tires in that style?
Leo
Some say running a rear on the front is ok if you reverse the direction of rotation arrow.
Doesn't Avon make front tires in that style?
Leo
Murdock
XS650 Member
The rears are called Safety Mileage and the fronts Speedmaster. They have a different tread and shape as far has I know. I should have pointed out I want the fat tyre look. I assumed that look was by fitting a reversed rear tyre on the front?
Hi Murdock,
it'll look like your sidecar fell off.
it'll look like your sidecar fell off.
Murdock
XS650 Member
Ok so what do folk fit for that fat tyre brat look? The tyre I was thinking of is the one on the right on this link http://www.avon-tyres.co.uk/motorcycle/safety-mileage-mkii
Be prepared to get used to the new, interesting handling and cornering the fat front tyre will bring to the party.
Not saying it's dangerous or anything, just umm...interesting until you get used to it.
The fatter front changes the angles enough to cause some understeer on corners and it's easy to fall back into the old habits until the new ones are fully ingrained in you.
I fitted a fat front years ago, as it was all I could get at the time and that was interesting. I got into the habit of just making the bitch go around the corners, whether it felt like it or not, and when that tyre finally wore out, I was glad.
Putting a normal sized tyre on was like greeting an old friend and going out for a beer.
One thing I could have tried, but never thought of it at the time - to compensate for the trail alteration, I might have dropped the yokes on the fork legs by half an inch or so and perhaps regained some of the steering quickness that had been lost.
ps. it might be worth your while having a look and asking over at the Darkside Forum, where putting a rear on the front isn't unknown. Some there might have some useful advice.
http://forums.delphiforums.com/n/main.asp?webtag=darksiding&ctx=128&cacheTag=x32-29
It's a weird forum setup, but you get used to it; just like a fat front
Not saying it's dangerous or anything, just umm...interesting until you get used to it.
The fatter front changes the angles enough to cause some understeer on corners and it's easy to fall back into the old habits until the new ones are fully ingrained in you.
I fitted a fat front years ago, as it was all I could get at the time and that was interesting. I got into the habit of just making the bitch go around the corners, whether it felt like it or not, and when that tyre finally wore out, I was glad.
Putting a normal sized tyre on was like greeting an old friend and going out for a beer.
One thing I could have tried, but never thought of it at the time - to compensate for the trail alteration, I might have dropped the yokes on the fork legs by half an inch or so and perhaps regained some of the steering quickness that had been lost.
ps. it might be worth your while having a look and asking over at the Darkside Forum, where putting a rear on the front isn't unknown. Some there might have some useful advice.
http://forums.delphiforums.com/n/main.asp?webtag=darksiding&ctx=128&cacheTag=x32-29
It's a weird forum setup, but you get used to it; just like a fat front
angus67
Welder's penetrate deeper!!
Dark side is car tire on rear(I think)
Murdock
XS650 Member
Thanks a lot guys. I've decided to go for a 400x19 speedmaster front tyre on the front and a 500x16 Safety mileage on the rear. As Grimly will well know we have a lot of corners here in the UK, and I'm building this bike to be usable and safe.
On the subject of Darkside. My other bike is a Honda Valkyrie and many riders in the USA fit a rear car tyre. That's known has "Darkside". Also fitting a reversed rear tyre on the front is known has "Double darkside". We tend not to do that over here in the UK due to the fact it instantly voids your insurance if your not running correct M/C tyres. My XS will be insured has a custom with a specialist company.
On the subject of Darkside. My other bike is a Honda Valkyrie and many riders in the USA fit a rear car tyre. That's known has "Darkside". Also fitting a reversed rear tyre on the front is known has "Double darkside". We tend not to do that over here in the UK due to the fact it instantly voids your insurance if your not running correct M/C tyres. My XS will be insured has a custom with a specialist company.
It wouldn't instantly void your insurance at all - that is illustrated by the number of cruiser riders using car tyres in the UK, perfectly legally.
Otoh, if the insco can prove your car tyre was directly responsible for the crash, they'd attempt to hang you out to dry. Probably pay up for third party losses and pursue the rider for the outlay.
Slightly different; we haven't become as bad as Germany and the TUV - yet. Although there are those in the EU who rub their sweaty little palms at the thought of everybody being under the jackboot of Brussels, it hasn't totally taken place.
Frankly, I'd rather run a car tyre than put another fat front on - that was much less pleasant, and it was quite legal, too.
It boils down to personal responsibility and common sense.
Otoh, if the insco can prove your car tyre was directly responsible for the crash, they'd attempt to hang you out to dry. Probably pay up for third party losses and pursue the rider for the outlay.
Slightly different; we haven't become as bad as Germany and the TUV - yet. Although there are those in the EU who rub their sweaty little palms at the thought of everybody being under the jackboot of Brussels, it hasn't totally taken place.
Frankly, I'd rather run a car tyre than put another fat front on - that was much less pleasant, and it was quite legal, too.
It boils down to personal responsibility and common sense.
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Murdock
XS650 Member
Your right of course your insurance wouldn't be instantly void. I should have said worst case scenario..
Perhaps I should clarify what I meant by "legally" - I can find nothing that says it's actually illegal to run a car tyre on a bike in the UK. The bike will fail an MoT with one fitted, so it's been addressed there, but despite looking I couldn't find anything relating to the prohibition of car tyres on motorcycles in the C&U Regs.
http://www.legislation.gov.uk/uksi/1986/1078/contents/made
Perhaps a closer scrutiny is in order. I'm open to correction on this, and even though it doesn't affect me directly, it would be good know for sure. There is no shortage of hand-wavers and outside-toilet lawyers, and even some legalists who ought to know have often been found to spout total BS on other matters.
Over here, the issue is avoided by there simply not being an MoT for bikes, but if I were to fit a car tyre I'd be careful about it, and not ask too much of it, unless and until I was dead sure of its characteristics.
Anyway, my dead-sure recollection of the 60s and 70s is seeing Avon car tyres of 5.00 x 16 size on the back of various chops and they never caused the slightest problem as far as I know. These chops were the fore-runners and design inspiration of the very same Specials we all know here - and guess what size tyre will fit straight on the back of a Special? At the time, there was no mention in the MoT of car tyre use on motorcycles, and even though it was a bit of a non-issue, there was pressure to legislate about it from control freaks, so it was sneaked into the MoT, under the guise of 'safety', which as far as I can see is nothing but a load of old cobblers.
Unfortunately, there is no easily-available or cheap radial car tyre in that size, so I'm wondering if I may emulate the old chopper riders and simply fit a vintage-sized car tyre of crossply structure - probably no worse off for general grip and roadholding, but it remains to be seen if the same benefits of long mileage can be got from a crossply car rear as from a radial. I kind of doubt the mileage benefits, and if there's none, I'd be inclined to try it out and not bother repeating it. Otoh, if the mileage benefit is there, I'd stick with it.
Here's a UK example of an old-style Avon (or similar)
http://www.therevcounter.co.uk/thre...-the-Dark-Side?p=419986&viewfull=1#post419986
Fwiw, my other ride, a GS850, will shortly be fitted with a 135R15 car rear, courtesy of a Suzuki Cavalcade rear wheel, once I sort out the bearing / axle match-up.
http://www.legislation.gov.uk/uksi/1986/1078/contents/made
Perhaps a closer scrutiny is in order. I'm open to correction on this, and even though it doesn't affect me directly, it would be good know for sure. There is no shortage of hand-wavers and outside-toilet lawyers, and even some legalists who ought to know have often been found to spout total BS on other matters.
Over here, the issue is avoided by there simply not being an MoT for bikes, but if I were to fit a car tyre I'd be careful about it, and not ask too much of it, unless and until I was dead sure of its characteristics.
Anyway, my dead-sure recollection of the 60s and 70s is seeing Avon car tyres of 5.00 x 16 size on the back of various chops and they never caused the slightest problem as far as I know. These chops were the fore-runners and design inspiration of the very same Specials we all know here - and guess what size tyre will fit straight on the back of a Special?
At the time, there was no mention in the MoT of car tyre use on motorcycles, and even though it was a bit of a non-issue, there was pressure to legislate about it from control freaks, so it was sneaked into the MoT, under the guise of 'safety', which as far as I can see is nothing but a load of old cobblers.Unfortunately, there is no easily-available or cheap radial car tyre in that size, so I'm wondering if I may emulate the old chopper riders and simply fit a vintage-sized car tyre of crossply structure - probably no worse off for general grip and roadholding, but it remains to be seen if the same benefits of long mileage can be got from a crossply car rear as from a radial. I kind of doubt the mileage benefits, and if there's none, I'd be inclined to try it out and not bother repeating it. Otoh, if the mileage benefit is there, I'd stick with it.
Here's a UK example of an old-style Avon (or similar)
http://www.therevcounter.co.uk/thre...-the-Dark-Side?p=419986&viewfull=1#post419986
Fwiw, my other ride, a GS850, will shortly be fitted with a 135R15 car rear, courtesy of a Suzuki Cavalcade rear wheel, once I sort out the bearing / axle match-up.
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Hi Grimly,
16" car tires and 16" bike tires have the exact same bead diameter.
I ran 125/85-16 TwinTires (two narrow tires on a common rim, a fad that didn't last) on the back of my XS11 & XS650 sidecar rigs, they wore like iron but alas they don't make them any more so I'm back to running my rigs on 5,000-miles-'til-they-go-bald bike tires because the skinniest 16" tubeless car tire I can find is a 185/80 which is way too fat to fit in the swingarm.
But the tiremakers ain't finished screwing with us yet.
15" (and as far as I can discover, only 15") car tires have a 1/8" smaller bead diameter than 15" bike tires.
Some have managed to force a 15" car tire onto a 15" bike rim but I'd say stretching the bead wires that much would compromise the tire's integrity and I wouldn't recommend doing it.
I'm waiting to see whether I need to have the rim machined a bit or not. This tyre doesn't seem to give problems, according to to others on the darkside list of fittings, with seating pressures quite low. However, that was on PC800 and suchlike and the Cavalcade doesn't get a mention, but since it's a standard rim size I suspect it might be fine.
The other holdup is finding a disc - so few of them were sold the discs are now rare-ish. I can have one made locally, so if push comes to shove I'll do that.
Hi Dave,
there was considerable "darkside" discussion on the SCT sidecar site as sidecar tugs just don't need round profile tires and are OK with trading bike tire grip for car tire longevity.
Consensus was that "if it'll fit it'll work".
Thing is, 15" car tires DON'T fit 15" bike rims because 15" car tires and rims are made 1/8" smaller than 15" bike tires and rims.
OK, you can stretch the bastards on but I reckon that's dodgy.
I'd suggest that before you commit money and time to going 15" darkside you measure the bead circumference of a 15" bike rim and of a 15" car rim and base your decision on the numbers.
It took long enough, but there it is.
The rim was one I stumbled across at the start of the year - it's one that was made up for a sidecarist to allow him/her to use 15" car tyres on his GS850 or 1000 shafty.
The Michelin 135 that was on it was barely worn, but quite old, so it got the heave and I fitted a Nankang CX668 135/80-15.
Only drawback to it is the reduction in overall gearing, with the bike sitting @ 6Krpm when only going 70mph.
However, I'll see how long it lasts.
I've discovered that Michelin are still making the Michelin X tyre in 5.50R16, and I suspect that might just squeeze into the swingarm mounted on the GS1100G wheel I have. If that fits, the gearing will be corrected.
The rim was one I stumbled across at the start of the year - it's one that was made up for a sidecarist to allow him/her to use 15" car tyres on his GS850 or 1000 shafty.
The Michelin 135 that was on it was barely worn, but quite old, so it got the heave and I fitted a Nankang CX668 135/80-15.
Only drawback to it is the reduction in overall gearing, with the bike sitting @ 6Krpm when only going 70mph.
However, I'll see how long it lasts.
I've discovered that Michelin are still making the Michelin X tyre in 5.50R16, and I suspect that might just squeeze into the swingarm mounted on the GS1100G wheel I have. If that fits, the gearing will be corrected.
From what I understand there is a rim specifically made to lace on a Harley hub so car tires can be used on the big land barges Harley makes. Hot sur te size of the rim or the tire they use.
Knowing that finding a car tire that would fit inside the swing arm of an XS650 would be tough I didn't research it very far.
Leo
Knowing that finding a car tire that would fit inside the swing arm of an XS650 would be tough I didn't research it very far.
Leo
Hi Leo,
I tried to find a square-section rear tire for my sidecar outfit.
Lots of 5"-16 square section tires out there for antique cars but not one of 'em would run tubeless.
Resigned myself to running el-cheapo Cheng-Shins on my XS650 rig's back wheel and living with their short road life.
The various tyre makers in Europe have been re-introducing skinny tyres for classics and modern eco-boxes.
That one on mine is a 135/80r15, but it's a bit short geared, so I can try a 145/80r15 which will bring it a bit closer to factory gearing. I think that's about as far as I can go, given the space in the swingarm. If that fits and leaves some room I can try a 155/80r15. There's a 165/80r15 which would be perfect, but it's probably too wide, even mounted on the 3" rim.
Those are all cheap enough to try.. What I might do is go around the tyre depots and dig out some used tyres for comparison purposes. All of these are tubeless, btw.
I have a 16" wheel for that bike, but can't find a suitably skinny 16" tyre, although the temptation of that Michelin is strong, but I don't want to spend 200 smackers anyway, and even if I did, then find it's rubbing the swingarm...so that's money down the drain.
Apart from that, it's an ancient design of Michelin-X, and even though it's made with modern compounds, the tread design is inferior to modern tyres.
When it comes to the XS, I have a reasonable choice from the 15" tyres if I fit a suitable rim and alter the chain sprockets to suit.
ps. the smaller 15" tyre makes the ratbasket acclerate well.
That one on mine is a 135/80r15, but it's a bit short geared, so I can try a 145/80r15 which will bring it a bit closer to factory gearing. I think that's about as far as I can go, given the space in the swingarm. If that fits and leaves some room I can try a 155/80r15. There's a 165/80r15 which would be perfect, but it's probably too wide, even mounted on the 3" rim.
Those are all cheap enough to try.. What I might do is go around the tyre depots and dig out some used tyres for comparison purposes. All of these are tubeless, btw.
I have a 16" wheel for that bike, but can't find a suitably skinny 16" tyre, although the temptation of that Michelin is strong, but I don't want to spend 200 smackers anyway, and even if I did, then find it's rubbing the swingarm...so that's money down the drain.
Apart from that, it's an ancient design of Michelin-X, and even though it's made with modern compounds, the tread design is inferior to modern tyres.
When it comes to the XS, I have a reasonable choice from the 15" tyres if I fit a suitable rim and alter the chain sprockets to suit.
ps. the smaller 15" tyre makes the ratbasket acclerate well.
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- - - . the smaller 15" tyre makes the ratbasket acclerate well.
Hi Grimly,
you can also boost an XS650's acceleration by sprocket swapping.
My Heritage Special left the factory with 17/36 sprockets.
Zero to street speed acceleration, real good, highway speed, vibration-limited to ~ 70mph.
Swapped to 17/34 to get rid of the 4-speeed + underdrive ride characteristics.
Swapping to 17/38 when the chair was added took the rig back into underdrive.
Carefully saving the 36T sprocket paid off as 17/36 works perfectly on my sidecar outfit.
