Tyre size choice on a K100
Andy Hewitt
Bridgestone BT45s. The standard tyre size is 130/90/17, but the BMW
manual also ays it can take a 140/80/17 too.
Is there any benefit in changing to the 140/80?
--
Andy Hewitt ** FAF#1, OSOS#5 - BMW K100RS 8v, Honda Concerto 16v
Windows free zone (Mac G3)
<http://homepage.ntlworld.com/ahewitt/index.htm> (last update 12.02)
Hog
news:1funnoc.1id48hb1x6ww8nN%hairy...@spamcop.net...
> It's time for a new rear tyre for the old girl, and I usually stick to
> Bridgestone BT45s. The standard tyre size is 130/90/17, but the BMW
> manual also ays it can take a 140/80/17 too.
>
> Is there any benefit in changing to the 140/80?
You can go up 10mm front and rear but I don't think it's going to benefit
much. Go with what size is cheapest?
--
Hog
hog...@ukrm.net (remove bondage to reply)
'89 R100RS '96 K1100LT '02 GSXR1000K2
Andy Hewitt
> "Andy Hewitt" <hairy...@spamcop.net> wrote in message
> news:1funnoc.1id48hb1x6ww8nN%hairy...@spamcop.net...
> > It's time for a new rear tyre for the old girl, and I usually stick to
> > Bridgestone BT45s. The standard tyre size is 130/90/17, but the BMW
> > manual also ays it can take a 140/80/17 too.
> >
> > Is there any benefit in changing to the 140/80?
>
> You can go up 10mm front and rear but I don't think it's going to benefit
> much. Go with what size is cheapest?
That'll do for me, the 130 is a fiver cheaper. I was wondering if the
140 might give slightly better wear, the last tyre managed about 5000
miles.
Hog
> Hog <hog...@ukrm.net> wrote:
>
> > "Andy Hewitt" <hairy...@spamcop.net> wrote in message
> > news:1funnoc.1id48hb1x6ww8nN%hairy...@spamcop.net...
> > > It's time for a new rear tyre for the old girl, and I usually stick to
> > > Bridgestone BT45s. The standard tyre size is 130/90/17, but the BMW
> > > manual also ays it can take a 140/80/17 too.
> > >
> > > Is there any benefit in changing to the 140/80?
> >
> > You can go up 10mm front and rear but I don't think it's going to
benefit
> > much. Go with what size is cheapest?
>
> That'll do for me, the 130 is a fiver cheaper. I was wondering if the
> 140 might give slightly better wear, the last tyre managed about 5000
> miles.
It's not going to wear better really, more about maximum grip on the lean.
Not a big issue with a K.
Oh, the wrong tyre sizes can make them weave even more too.
Steve Parry
> It's time for a new rear tyre for the old girl, and I usually stick to
> Bridgestone BT45s. The standard tyre size is 130/90/17, but the BMW
> manual also ays it can take a 140/80/17 too.
>
> Is there any benefit in changing to the 140/80?
Radial tend to come in the 140/80 x 17 size rear and 110/80 x 18 front
I've had the new Avon Azaro ST 45 110/80ZR18 front and the ST46 140/80ZR17 rear for the
past two tyre changes and out of all the tyres I have ever had on a K I've never found
any that grip and "suit" the bike as well as these ... just wonder if I can get Avon to
pay for the replacemtn stands, belly pan and footrests that thier products are helping to
shave ;o)
--
Steve Parry
http://www.gwynfryn.co.uk
http://bmwmotorcycles.tripod.com
http://wrexhamseals.tripod.com
Hog
news:b9eduj$ikqgh$1...@ID-190837.news.dfncis.de...
> Andy Hewitt wrote:
> > It's time for a new rear tyre for the old girl, and I usually stick to
> > Bridgestone BT45s. The standard tyre size is 130/90/17, but the BMW
> > manual also ays it can take a 140/80/17 too.
> >
> > Is there any benefit in changing to the 140/80?
>
> Radial tend to come in the 140/80 x 17 size rear and 110/80 x 18 front
>
> I've had the new Avon Azaro ST 45 110/80ZR18 front and the ST46 140/80ZR17
rear for the
> past two tyre changes and out of all the tyres I have ever had on a K
I've never found
> any that grip and "suit" the bike as well as these ... just wonder if I
can get Avon to
> pay for the replacemtn stands, belly pan and footrests that thier products
are helping to
> shave ;o)
Hmm, well I have no experience of these tyres so I cannot comment. I will
say that the rims of the K100 series are for crossply, BMW do not recommend
radials AKAIK. My understanding is that a radial tyre of a given size
matches a different span rim width than a crossply of the same size? For
the K1100LT perceived wisdom is that to run radial tyres you have to fit
K1100RS rims which have a wider span.
Are you vouching for a faired K model these tyres at speeds up to top speed,
slow and fast cornering with and without luggage - no weave or other
instability developing? be bloody sure about this before claiming so.
Andy Hewitt
<Snipped Text>
> > That'll do for me, the 130 is a fiver cheaper. I was wondering if the
> > 140 might give slightly better wear, the last tyre managed about 5000
> > miles.
>
> It's not going to wear better really, more about maximum grip on the lean.
> Not a big issue with a K.
LOL, indeed. Although I do get the cissy line almost round to the
sidewall.
> Oh, the wrong tyre sizes can make them weave even more too.
Bum, not something I need. Although I recently sorted that by replacing
the knackered 'Progressive' rear shock [1][2] with shiny new Hagon.
Thanks for the response.
[1] which was too long anyway, the back end now sits about 2 inches
lower with the Hagon, which is marked as a 'standard' length.
[2] it exploded oil out in quite a spectacular fashion.
Andy Hewitt
> Andy Hewitt wrote:
> > It's time for a new rear tyre for the old girl, and I usually stick to
> > Bridgestone BT45s. The standard tyre size is 130/90/17, but the BMW
> > manual also ays it can take a 140/80/17 too.
> >
> > Is there any benefit in changing to the 140/80?
>
> Radial tend to come in the 140/80 x 17 size rear and 110/80 x 18 front
>
> I've had the new Avon Azaro ST 45 110/80ZR18 front and the ST46 140/80ZR17
> rear for the past two tyre changes and out of all the tyres I have ever
> had on a K I've never found any that grip and "suit" the bike as well as
> these ... just wonder if I can get Avon to pay for the replacemtn stands,
> belly pan and footrests that thier products are helping to shave ;o)
:-)
Grip is OK as a rule, fitting the right (and working) shock seems to
have made most difference.
I do find the drift on long high speed corners a bit unnerving though.
Cheers.
Steve Parry
radials are on the list of recommended tyres under the seat, (K100RS SE 8 vallve)
dunlop, pirelli and bridgestone, I think. Although the models of tyres on the list are no
longer available ... not usprising given the list is about 15 years old now :o)
The last ones I used before the Avons, were Dunlop K105F (110/80VR18) and Dunlop K700 rear
(140/80VR17)
(which I think in different sizes were also stock tyres on Kawa GTR's)
http://www.tiresnstuff.com/dun-k700,k105,k701.html
North Wales police used these on their K100LT's too
I can take a digi pic of the underseat advice sticker if it helps.
Steve Parry
> Steve Parry <k100r...@nospamhotmail.com> wrote:
>
>> Andy Hewitt wrote:
>>> It's time for a new rear tyre for the old girl, and I usually stick
>>> to Bridgestone BT45s. The standard tyre size is 130/90/17, but the
>>> BMW manual also ays it can take a 140/80/17 too.
>>>
>>> Is there any benefit in changing to the 140/80?
>>
>> Radial tend to come in the 140/80 x 17 size rear and 110/80 x 18
>> front
>>
>> I've had the new Avon Azaro ST 45 110/80ZR18 front and the ST46
>> 140/80ZR17 rear for the past two tyre changes and out of all the
>> tyres I have ever had on a K I've never found any that grip and
>> "suit" the bike as well as these ... just wonder if I can get Avon
>> to pay for the replacemtn stands, belly pan and footrests that thier
>> products are helping to shave ;o)
>
> :-)
>
> Grip is OK as a rule, fitting the right (and working) shock seems to
> have made most difference.
>
> I do find the drift on long high speed corners a bit unnerving though.
>
> Cheers.
since changing to the azaros I've not noticed any drift ... in fact all the radials were
better in this respect.
Andy Hewitt
<Snipped Text>
> > Grip is OK as a rule, fitting the right (and working) shock seems to
> > have made most difference.
> >
> > I do find the drift on long high speed corners a bit unnerving though.
> >
> > Cheers.
>
> since changing to the azaros I've not noticed any drift ... in fact all
> the radials were better in this respect.
Righto. Unfortunately I'm not up for a pair this time, so I'll prolly
have to stick to the BT45 for now.
The Older Gentleman
<snip>
Cheng Shins. YKIMS.
--
XJ900S 750SS SR500 CB400F ST70 GAGARPHOF#30
GHPOTHUF#1 WUSS#5 YTC#3 IHABWTJ#1 BOTAFOT#60 ANORAK#06 OSOS#1
BOF#30 www.btinternet.com/~Chateau.Murray/homepage2.html
Hog
> radials are on the list of recommended tyres under the seat, (K100RS SE 8
vallve)
> dunlop, pirelli and bridgestone, I think. Although the models of tyres on
the list are no
> longer available ... not usprising given the list is about 15 years old
now :o)
>
> The last ones I used before the Avons, were Dunlop K105F (110/80VR18) and
Dunlop K700 rear
> (140/80VR17)
>
> (which I think in different sizes were also stock tyres on Kawa GTR's)
> http://www.tiresnstuff.com/dun-k700,k105,k701.html
>
> North Wales police used these on their K100LT's too
>
> I can take a digi pic of the underseat advice sticker if it helps.
I'm not trying to call you a liar!!
Late model RS, hmm, could be a different rim to the RT/LT even then but the
tyres it quotes (dredges memory) were they not the early bias belt so called
radials? yeah, I think I remember them on K100RS's but not recommended on
RT's.
What rim sizes do you have? a move to modern radials has to be good. I've
just moved the R100RS of the ancient Metzler design onto BT45's.
Steve Parry
PS
http://www.flyingbrick.de/Home__GB_/Types/Modifications/modifications.html
the Motorsport had radials back in 1986, I think they were Pirelli MP7R's if memory serves
me right.
A pic of my model KRS from Mick Walker and Peter Dobson book on the K series is on my site
and clearly shows the Pirelli MP7R radial tyres
http://bmwmotorcycles.tripod.com/images/krssemono.jpg
Steve Parry
oddly enough the rims on the RS and the RT/LT are exactly the same .. but I do seem to
recall that BMW did'nt recommend radials for the RT/LT faired version.
In fact ISTR being told that radials were a match with the "sports pak" front suspension
But North Wales plod used radials on thier K's .. at one time too though.
Steve Parry
> Andy Hewitt <hairy...@spamcop.net> wrote:
>
> <snip>
>
> Cheng Shins. YKIMS.
Hung Ha Swallows ..... as a spotty inexperienced yoof I fitted some of these to my RD400
during a time of severe dole induced poverty .... my normal choice of Dunlop TT100 's were
out of the price range ..
The Swallows lasted a week before the tread challenged dunlops went back on ....
Teflon coated tyres they felt like ;o)
Steve H
> Andy Hewitt <hairy...@spamcop.net> wrote:
>
> <snip>
>
> Cheng Shins. YKIMS.
Heh.
Surely you mean 'Maxxis' ;-)
--
Steve H
http://www.italiancar.co.uk - Honda VFR800
VW Golf GL Cabrio - Alfa 33 16v - Alfa 33 1.7ie
BoTAFOT #87 - BoTAFOF #18 - MRO # - UKRMSBC #7 - Apostle #2 - YTC #
Andy Hewitt
> Andy Hewitt <hairy...@spamcop.net> wrote:
>
> <snip>
>
> Cheng Shins. YKIMS.
Yeah, right. :-/
Alan T Gower
"Hog" <hog...@ukrm.net> wrote in message
news:b9ea4t$ie8k8$1...@ID-105725.news.dfncis.de...
> "Andy Hewitt" <hairy...@spamcop.net> wrote in message
> news:1funnoc.1id48hb1x6ww8nN%hairy...@spamcop.net...
> > It's time for a new rear tyre for the old girl, and I usually stick
to
> > Bridgestone BT45s. The standard tyre size is 130/90/17, but the BMW
> > manual also ays it can take a 140/80/17 too.
> >
> > Is there any benefit in changing to the 140/80?
>
> You can go up 10mm front and rear but I don't think it's going to
benefit
> much. Go with what size is cheapest?
I had considered going to 120 60 17 on my Gixer but it would upset the
handling too much. I've already dropped the forks by 5mm and the 10mm
reduction would have made it unstable at speed. It would turn quick
though ;).
--
Alan
GSX-R1000 , Triumph Thunderbird, ZXR750L2 Racer, CG125, GHPOTHUF#27
TGF, UKRMFBC#7, Two#24, BOTAFOF#11, YTC#9, GYASB#1. SbS#23.
DFWAG#2, DS#2, DIAABTCOD#20. NOSPAM in the reply
http://sportsbike.org (our own endurance team) http://Team-ukrm.com
"Nemo repente fuit turpissimus"
Hog
> the Motorsport had radials back in 1986, I think they were Pirelli MP7R's
if memory serves
> me right.
Dat's the fuckers, early attempt and crap. Right here is some interesting
stuff, and the K1100 RS/LT have different rims but the 2valve 100's don't.
http://www.bmw-club.org.uk/avon.html
http://www.bmw-club.org.uk/ktyres.html
Steve Parry
> "Steve Parry" <k100r...@nospamhotmail.com> wrote in message
> news:b9eh7t$ikip5$1...@ID-190837.news.dfncis.de...
>
>> the Motorsport had radials back in 1986, I think they were Pirelli
>> MP7R's if memory serves me right.
>
> Dat's the fuckers, early attempt and crap. Right here is some
> interesting stuff, and the K1100 RS/LT have different rims but the
> 2valve 100's don't.
>
> http://www.bmw-club.org.uk/avon.html
> http://www.bmw-club.org.uk/ktyres.html
Yes I knew the 1100's have different size rims to the 1000 (8valves)
I had a lot of help from one of Avons senior tyre guys ... Leo something ... very helpful
guy, who also confirmed the suitability of the ST45/46 's. I honestly cannot overstate
their stability in corners, first tyre I've ever had on the K that I've felt comfortable
having zero chicken strips on 'o)
I've seen the list on the BM club site ... problem is its so out of date nowadays, as is
the BM list as most of the tyres don't exist anymore. They've been on that site for years
without updating.
BTW I know you were'nt calling me a liar ;o)