Shortest Wheelbase ever on a BMW??

[Dr. Curve]

Just curious brothers, is the new 1000RR to be the shortest wheelbase BMW bike ever built?? It is coming through with just under 56 inches of wheelbase. How does that rank in the annals of BMW bike making? TIA

[NakedRider]

Must be the shortest of any of the current models. If my memory is correct even the F800 is about 58.

That's a short bike for a BMW.

[Highlander179]

Its competition;
CBR1000RR 55.6in
Duc 1098 55.6in
GSXR1000 55.7in
Yama R1 55.7in

[geothepencil]

I can't find the wb number, but that Ron Wood F800 Flat tracker looks pretty short. I hope to see it this weekend at Springfield. Of course thats not a production model.

geo

[Droptarotter]

What about a short wheelbase /5? Anyone?
Cheers,

[roger albert]

I always call those 56 in my head, but I think they're actually about 56-1/4

[Dr. Curve]

Double check Roger, my mind clicks right at 58" on the /5...........but could be wrong. The stability of the Ducati Darmah (true mag wheels, gear desmo, stepped advance, ect) amazed some of us with it's 61 inch wheel base in 1977. Perhaps the /5 was 56 inchs.........anybody got a conversion table and the info?

[GotRoad?]

[Dr. Curve]

Boy was I ever wrong.....................
1970 R75 Wheelbase........54.5 inches!! No wonder them things would turn on in! The /6 with its longer swing arm took things on out inchwise..... but for now the new bike IS NOT the shortest wheel base yet..............but it's (1000RR) HP to inch of wheelbase ratio (HP/WB) is going to be very high.......much more so than any previous BMW.

[Clutch Cargo]

My first BMW was a 1971 R75/5 swb. See this link for specs http://jeff.dean.home.att.net/r75-5.html Look at the "Dimensions and Weights" section towards the bottom.

[roger albert]

Interesting. I went out and measured a SWB /5 and do in fact get 56.25ish, BUT, that is the centerstand measurement, i.e. with suspension unloaded. Loaded, it would shorten, but no where near 2". Not quite how sure to reconcile actual measurements with factory specs, other than to say factory specs are often published wrong.

[Dr. Curve]

Roger, you must not have one with the short swing-arm like they came with from 1970 till mid 1973........at which point they lengthened the arm. You did know you have a long swing-arm........do you not?

[Dr. Curve]

I think that BMW offered measurments taken when the wheels were both in mid range of movement. If one has a SWB /5 on the center stand and measures it (WB)..........and then gets on the bike and pushes it off the center stand...............and has someone else measure the WB with the bike now half loaded..........it can easily be 2 inches less.......or more. Try it, you'll see. I would have never thought it either.

PS: Must also be that the bikes now have such steeper steering head angles, which means wheelbase changes less when hard braking compresses the shocks.

[roger albert]

> Roger, you must not have one with the short swing-arm like they came with from 1970 till mid 1973........at which point they lengthened the arm. You did know you have a long swing-arm........do you not?

The particular bike is a young lady customer's SWB '71 R50/5. Weird, I had two of those in the shop at once last week, vs once ever in the past. 50/5s are none too common.

Yes, modern bikes have steeper steering heads, so there is less difference. I could still only measure just over 1" delta-wheelbase from centerstand to very sagged. So, it fits with the hundreds of other bikes I've measured - way less than 2" differential. I can get 2" going from full extended to nearly full compressed, but surely that's not how anyone measures.
(and I can tell you from experience, the factories are often wrong, and very clearly don't all measure it the same way -- not even within a given factory, much less between them)

Interesting topic just the same.