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BT45 Tyre Size Query

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Tonto
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BT45 Tyre Size Query

#1 PostAuthor: Tonto » Mon Jan 12, 2015 6:18 pm

Chaps - Ive been pleased with the BT45's I fitted to my Z900 A4, but I'll soon be due for a new rear tyre and was wondering if I could get away with fitting a slightly wider tyre ?
I have standard Rims and currently run a 120/90 x 18, but was not sure if I could get away with fitting a 130/80 x18 ? :?? :??

I know its not a big difference, but I've got the wider BT45 fitted on another old Kwak and the "turn in" feels a lot nicer.
Any guidance appreciated. Cheers Tim
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#2 PostAuthor: jimmock » Mon Jan 12, 2015 6:35 pm

A 130 means the chain guard MUST come off.
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#3 PostAuthor: chrisu » Mon Jan 12, 2015 9:16 pm

check the tyre to chainguard clearance.

can you cope with another 5mm ?
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#4 PostAuthor: jimmock » Mon Jan 12, 2015 9:19 pm

chrisu wrote:check the tyre to chainguard clearance.

can you cope with another 5mm ?


ADMIN, COME ON.....


That was a sexually motivated question.
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#5 PostAuthor: Tonto » Tue Jan 13, 2015 11:43 am

Thanks guys: I thought it was going to be tight, but had not given the chainguard serious consideration Doh !! :vstoopid
I'll take some proper measurements before buying my new tyre.
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#6 PostAuthor: chrisu » Tue Jan 13, 2015 4:30 pm

jimmock wrote:
chrisu wrote:check the tyre to chainguard clearance.

can you cope with another 5mm ?


ADMIN, COME ON.....


That was a sexually motivated question.


Jim - are really expecting me to moderate myself ? ......... :roll:
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#7 PostAuthor: scott » Wed Jan 14, 2015 8:12 am

If you did go for the slightly wider tyre, what effects would it have on handling, especially higher up the mph scale?
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#8 PostAuthor: jimmock » Wed Jan 14, 2015 8:15 am

chrisu wrote:
jimmock wrote:
chrisu wrote:check the tyre to chainguard clearance.

can you cope with another 5mm ?


ADMIN, COME ON.....


That was a sexually motivated question.


Jim - are really expecting me to moderate myself ? ......... :roll:


That sounds sexual ??
Jimmock. :wnkr





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#9 PostAuthor: mick znone » Wed Jan 14, 2015 8:32 am

could always buy a spare chainguard and cut it down.
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#10 PostAuthor: Chris Riv » Wed Jan 14, 2015 12:01 pm

scott wrote:If you did go for the slightly wider tyre, what effects would it have on handling, especially higher up the mph scale?


I had a Z1 with a 150 rear tyre. It was ok when the tyre was new but as the profile flattened off it started to weave badly above about 80mph. It was otherwise a standard bike. I got round it by fitting Z650 yokes (more trail) & this moved the weave to about 110mph.
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#11 PostAuthor: Tonto » Wed Jan 14, 2015 12:01 pm

Just checked and Ive got a 12mm gap between inner edge of chainguard (which is a dodgy pattern replica :lol: ) and existing 120 tyre, I'll re-check swingarm clearance, but it does look promising for fitting a 130 replacement.
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#12 PostAuthor: njwmct » Wed Jan 14, 2015 1:55 pm

Stick with the standard tyre size as that suits the wheel rim width. A wider tyre is more than likely going to spoil the feel/handling of your bike.
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