pros/cons of wheel base length

[43%burnt]

i got my hands on a 2011 675r rear swing arm that has the additional 10mm or so of chain adjustment on it. what are the pros/cons of running a longer wheel base? i understand that stability improves, yet turn in suffers. anyone trying playing with this? thoughts? thanks guys.

[TRMN8TR]

I wasn't aware that the R had more room for adjustment in the swingarm? I think you pretty much nailed it though, lengthen the wheelbase for more stability, shorten it for quicker turn in. Try it out and see what you think.

[AussieAdam]

I've read that longer swing arms give you better traction accelerating out of corners also.

[TwoWheeledWonder]

Originally Posted by TRMN8TR

I wasn't aware that the R had more room for adjustment in the swingarm? I think you pretty much nailed it though, lengthen the wheelbase for more stability, shorten it for quicker turn in. Try it out and see what you think.

I dont think it is just the R I am pretty sure they made one year longer than the previous years, but forget when it started. May have been 09+, but not 100% on that.

[bmw4422]

I thought it was just the casting after the axle that was longer. Iirc, that's why some with the "r" we're having issues with the lightech chain adjusters.

[Leebean01]

Originally Posted by bmw4422

I thought it was just the casting after the axle that was longer. Iirc, that's why some with the "r" we're having issues with the lightech chain adjusters.

I have the lightech adjusters for my r but haven't installed them yet. We'll have to see how it goes.

[BMAF]

turn in doesn't have anything do with wheel base. That's solely front end geometry. Now adding/taking away length will add/remove stability. Unicycle or 18wheeler on track. You have to find the middle ground that fits your riding style and your equipment.


Umicheng told me Dave Moss said to her: right in the middle is great for our bikes.

[Triumph Race Support]

The 675 in the hands of a top rider is critical to wheelbase length.
The longer the wheelbase the more stable the bike is mid corner, thats the key point in the corner not in a straightline. As pointed out BMAF the wheelbase don't make a difference going into the corner. Thats all taken care of by rake & trail on the front forks. I prefer a short wheelbase to allow the bike to feel light in a corner, the longer wheelbase makes it feel very planted. I had a customer yesterday calling about his Fireblade shredding back tyres. He had added 2 teeth to his back sprocket and of course shortened the wheelbase which in turn led to the rear tyre spinning up more and shredding tyres. Theres so much to geometry people have wrote complete books in it. You have to find what works for you. Get the bike turning in and flicking from side to side right and then work on wheelbase for the mid corner feeling.
I'm not going to give away the optimum wheelbase but I will tell you this we had to use ecentric adjusters in the front axle on the 675R to get it to handle right!

[BMAF]

oh, c'mon mate! Spill the beans. We all want that magic number. Lol

[dubguy85]

Originally Posted by BMAF

oh, c'mon mate! Spill the beans. We all want that magic number. Lol

I have heard from multiple sources that with aftermarket triples, forks to flush a good starting point is 583mm from the center of the swing arm pivot to the center of the rear axle.

That being said everyone likes different set ups and people ride motorcycles different.