BMW R1200R R1150R/T F800 K1200R R1100R/T R1250R RnineT Message Board

Tyre choices affect handling. If I installed a 130/60 instead of the standard 120/70 is this likely to have any crazy effects?

It's not a massive and radical change but its worth checking. The bike handles well and has no nasty habits and I don't want to endanger that.

I am aware that it would require a 4" hub.

Regards,

Sol

It would probably slow the steering .
Noticeably.
Why do you want to do that?

Why...

I have been doing a custom conversion to an R1150. The final big job is the addition of spoked wheels.

I have the front and rear hubs. The mechanic has said that my calculations are correct and they will fit. I am now having them test fitted to absolutely ensure that everything is correct. When I have those assurances there two options.

1 - OEM rims (Excel H pattern road rims) to the matching widths 3.5x17 and 5x17 and then sealed for tubeless. Woody's Wheelworks can do this. they use a custom spoking pattern to make them stronger and have a supersized spoking option to further support that.

2 - Use factory BMW cross spoke rims but run 4x17 on the front (normally 3.5x17) and 4.5 x 17 (normally 5x17) on the back. This allows for the normal tyre on the rear and a slightly wider tyre on the front. The tyre size on the front would need to be 130/60. Since I already have a 4x17 cross spoked rim it would save some money. The new r1200GS uses the 4.5x17 cross spoked rim (US$552 from BMW) and runs the same 160/70 tyre as the R1150r.

Each option has advantages and disadvantages. I am trying to evaluate them to make an informed decision. Some disadvantages are of more concern than others. I have deliberately not made any changes to the steering geometry of the bike. It handles well and predictably. I know that changing the width of the front tyre will affect that.

My question is: considering the small change to the tyre dimensions, how great will the effect be, and is it something I would begin to accommodate after a short period of time.

I cannot afford to change the wheels after they are built so I want to cover every base and make the most informed decision possible before the build phase. The perfect solution would be 3.5x17 and 5x17 BMW cross spoked rims but they aren't available. A company in Italy called Kineo make a suitable product but the cost is exorbitant and consequently impractical. The Kineo rims look beautiful :-(

Regards,

Sol

OH,
regards, carry on.

M .
:-)

I wouldn't, personally.

120 is pretty wide for a front already.

Do you have link to de tire you want to use?

No. I had no specific tyre I just based it on the tyres that would fit a 4x17" rim.

Well, its dangerous to use rear in front. I was thinking about it my self:-)

Do you have pics of the bike?

People have been running rear tires on the front safely for years even on a track.
Generally you reverse mount a rear on the front meaning with the mounting arrows backwards.

A picture was requested........This is where I stand at the moment.

• - Air box gone
  - Black exhaust wrap in place
  - ...next stop wire wheels.....and if I get a rush of blood, I may rebuild the tail in aluminium and make it so that it sits a bit lower. (Not as big a rise behind the seat.)

I have heard folk complaining that the absence of an airbox seems to affect the running of the bike, haven't noticed any changes. ( Before everyone plays stacks on...I accept that K%Ns will not filter the air as well as a stock paper filter)

I wanted the big open underbody look.

Thumb up!

How will this airfilters behave on a rainy day?

Torsen,

I have little black covers on them made from a stretchy material that I sprayed with a water repellant product/ I have ridden it plenty of times in the rain and have never noticed any issues. It doesn't get babied either, I ride at least 300km a week on it summer and winter.

Rs,

Sol

I can imagine how great the bike will look with the spoked wheels!
That said, I would try to stay with the 120 front tire to maintain the steering feel you have now.
130 will make it "slower" or a bit sluggish.
Just my $.02 worth

On the basis of the support and feedback from forum members I have decided to maintain the same tyre sizes to avoid any handling changes. I like the way the bike handles at the moment and it worked out that rims in the correct sizes were available.

The hubs are at Woody's now and the next step is to get them back and get them fitted. I wanted black spokes but after much discussion the chaps at Woodt'y suggested there was not a reliable and durable solution that maintained the benefits of stainless steel. So SS it is.

Thanks to everyone for their help and commentary. I have had the hubs test fitted, I have done the calculations and everything should work. Even so I am still a little anxious.

Who dares wins!

The SS spokes will look fantastic!
I can imagine you want all black but I think the contrast of the spokes will really set off the whole look.
Trying to keep the blacked out spokes looking good would be a PITA and you would regret it down the road.
Good luck and post results

Soliton wrote:On the basis of the support and feedback from forum members I have decided to maintain the same tyre sizes to avoid any handling changes. I like the way the bike handles at the moment and it worked out that rims in the correct sizes were available.

The hubs are at Woody's now and the next step is to get them back and get them fitted. I wanted black spokes but after much discussion the chaps at Woodt'y suggested there was not a reliable and durable solution that maintained the benefits of stainless steel. So SS it is.

Thanks to everyone for their help and commentary. I have had the hubs test fitted, I have done the calculations and everything should work. Even so I am still a little anxious.

Who dares wins!

When I talked to them [Woody's] about it, they indicated that powder coated spokes will chip/crack/peel...after a time due to flexing ? Not sure about paint ? and forgot to ask about "black-chrome" .

As per the photo you have posted...that is a sharp looking motorcycle. Sure hope you post more after the wheel change....

Soliton wrote:Torsen,

I have little black covers on them made from a stretchy material that I sprayed with a water repellant product/ I have ridden it plenty of times in the rain and have never noticed any issues. It doesn't get babied either, I ride at least 300km a week on it summer and winter.

Rs,

Sol

How 'noisy' are the intakes ?

And what exhaust brand ? / combo ?