Confused about the tire sizes

I have just bought 100/90 Metzeler tires for my px200e but the tire seems wider than 3.50/10 as it is rubbung against the engine block. I’ve put spacers to the rim so it doesn’t seems rubbing at the moment but don’t know what will happen when the tire heats up… shouldn’t be 3.50 and 100/90 same…why do they differ???

If you have a current copy of the SIP classics catelogue there is a section all about tires and a small conversion chart which equates to 100’90-10 = 3.50-10. which doesn,t make sense unless you have a metzeler me 7-teen which is 120’90-10 in which case it is half an inch wider.Check the book out anyway.:shoot1:[:dance3:]

The only problem with 3.50/10 is that the speed rating is crap, 62mph, useless for use on a tuned machine that does motorway miles. I believe SIP do a tyre with a 120 kph speed rating that I will try next time.

100/90 are wider (100 mm = a bit less than 4 inches)

[?[] What did you do in the end? I want to know what size tyres you put on, did you space it or was it standard, because i am even more confused than you are now!!!

I know…I have this catalog…that’s why I’m confused…it’s a ME5…the rubbing is at both wheels. I don’t see any point why is the difference…The front tyre rubs to the plastic spring cover and the rear tyre rubs to the suspension springs and clutch cover…can I use the bike with the spacers in confidence or should I change the tires as soon as possible…

thanks in advance,

Under no circmustances ride with the tyre rubbing. The increased heat that is generated is likly to b*** the tyre out at high speed.

yes, 100/90 are wider than 3.50. They are actually the right tires for the Cosa…I think sip should correct this in their catalog.
I rode the bike with the spacers for a while but then I switched back to original sizes (3.50/10)…