Talk to me about tyres!

[warren3200gt]

I've got 2 650's, a 900 and a 1000 all with Avon RR's on them. Been running the for years and not found a better all round tyre.
Problem I now have is deciding which tyre to choose for a highly engine modded J2. Running 1100 top end.
Stock J2 tyres are front 3.25 x 19v, rear is 4.25 x 18v.
Front is no problem but widest rear avons made is 4.00.
Because of the mod's I'd rather go wider not narrower!
Rear rim is 18 x 2.15 stock J2.
So question is what are the guys with wider tyres running and how do they perform.
Looking for reccomendations.

[DeadZedDave]

Hello Warren the old 2.15 J rim is a bit limiting !
First idea would be to find a 2.50 wide rim from a GPz1100 B2 or an 1100R - same style as your J wheel - same spindle sprocket carrier /disc so an easy swap. A 130/-18 wide rear tyre sits nicely on these rims - some used to fit a 140 tyre but thats technically too big.
This wheel would look "stock". You also find the same wheel on late model /post 81 Police bikes - but check its a 2.5 before you buy !
After that you're looking at an aftermarket or custom set up. I think you can squeeze a 150 tyre on a 3.5 inch wide rim into the J swingarm.... An old Morris 3.5x18 7 spoke from an old race bike looks like a good match for the original J wheel but everything will need to be "made to fit" depending on what its been used on previously. Also these wheels are made from Magnesium Alloy and some say they the old Alloy can crack with age.... they don't come cheap either - if you can find one. I think you can buy them new for around £1400 - but that wouldn't be an option if it was me !
Another option is a pair of GPz750A unitrack wheels which are 18 inch front and rear with a 3 inch wide rim on the back. The spoke design is completely different as I know you will already know but these can be made to fit fairly easily. Rear spindle is only 17mm dia and you'd need a spindle from an early z650 or similar- plus some mods to the swingarm spindle slots /adjusters - but it can be done 130 - 140 - 150 tyres ? - looks a bit like Dymag style 3 spokes at a glance....
Be good to know how you get on !

[warren3200gt]

Thanks Dave but not really looking to swop out wheels from stock. Was really asking for options on, what's available in what sizes as tyre choices.

[DeadZedDave]

HaHa... no worries Warren but I have to say it.... that 2.5 rim will open up your tyre choice possibilities and help the handling and if you put your J2 wheel next to the Gpz11/1100R wheel, the only way you (or anybody else) will spot the difference is by checking the cast marks or removing the tyre to measure the width ! - asides from width, these wheels are identical !! I've used them on early Z'ds since the old days and nobody ever noticed - and theres more differences with the early wheels.... They just work better....

[warren3200gt]

To ask in another way, any members with a j1/2/3 or R1/2
what trye make and size are you using and what do you think of them?

[ADRIAN H]

Avon Road Riders MkII - 110/90 x 18 x 61V is available - which fits a rim 2.15 - 3.00 from the Avon chart on the link

https://www.avontyres.com/en-gb/tyres/r ... motorcycle

[warren3200gt]

Thanks Adrian. I just found Tyretec list a 120/90 roadrider mk2 which is apparently a direct conversion from 4.25v-18 listed as stock in the workshop manual.
My local guy said that Avon RR's weren't available that size so I'll go with tyretec and keep my fingers crossed.

[ADRIAN H]

Thanks Adrian. I just found Tyretec list a 120/90 roadrider mk2 which is apparently a direct conversion from 4.25v-18 listed as stock in the workshop manual.
My local guy said that Avon RR's weren't available that size so I'll go with tyretec and keep my fingers crossed.

You’re welcome.

[King of Kings]

Have a look at Conti Classic Attack radials, great tyres!