Wider rear tyres than standard ??

Hi all,
Its time to replace the tyres on my 1993 Cali 3.
Does anyone know if its possible to fit wider than the standard 120/90/18 's that I’m using now ??
Obviously there’s not a lot of spare room between tyre and drive shaft tube … (about 3/8" I reckon) and people have been telling me that the width profiles are different with different brands ?? … and that the only way is to fit them and see what happens, … which seems a bit daft to me.
I’m on Pirelli Sport Demons and fancy some Metzelers, but for some reason they don’t do 120’s only 130’s… ?? Will they go on without rubbing ??
If I have to stick with the 120’s … Any one got any thoughts on which tyres have the best grip ?
Thanks,

sorry just realised your bike is earlier than those listed in the guide so maybe clearances smaller

Hi sidthedid,

Thanks for your response re. tyre sizes for my 1993 Cali 3, …

I’ve had a look at the size listings in ‘Martyn’s Choice’ … and I’m having a spot of bother trying to understand the charts …
Firstly, … is it ok to put different tyre brands on front and rear ?? …Like his recommended Avon and Bridgestones?? . (I’ve always thought you should pair up the tread patterns or something?) …
Secondly,… am I reading the chart wrong or something, … as it seems that all the rear tyres listed are 17" ?? (mine are both18" alloys)… …Is the 17" rear an American spec or something ?
Interesting to see Martyn’s choice of 110 front and 140 rear !! … Blimey …
Also are these charts a bit out of date? … 'cos when I’ve looked recenly for some Metzelers … the ‘Laser’ and ‘Metronics’ are not listed anymore, … and the only 120’s I can find are for 16" …??

The reason I’m asking for advice on all this, … is that my local tyre guys are saying that I’d have to buy the 130’s of whatever brand … fit them on and see if they rub ! … If they do, … then I have to purchase another thinner 120 tyre.
Which at about a £100 a pop (plus labour fitting) … is an expensive way of doing it.

At this rate I might have to go with the Bridgestone BATTLAX BT-45 or something, … but I wonder why Metzeler don’t do a 120/90/18

Anyway, thanks a lot for your help … I’ll get there eventually!.

Ian.

he does state you can use a narrower tyre but it has to be different in another dimension to keep the Speedo accurate, it’s somewhere on the website but I can’t remember if it’s in the screenshots.

some of the tyres are no longer available, I did narrow my choice down to a pair of pirellis for my Cali off that guide that the tyre fitters could still get although it ended up I have not got them yet as bike is off the road for other reasons.

I found the tyres I have on were rubbing if air pressure was too low, slightly counter intuitive but putting more air in stopped them rubbing