Topic: Swingarm measurements, Questions, Swap

[Pwfyrcat1]

You know the nice thing about a slow project is it gives you time to change your mind about what you want to do.

But I am thinking about putting a slightly longer swingarm on my 400. I've read most of the articles on handling, etc.  But I don't plan on blasting around with it.

does anyone know of a swing arm that would swap out with the 400F?

Can someone/anyone, measure the width of the swingarm at the pivot point on the 550, 650, and 750?  That way, I would know how wide they are at the pivot point.

Yeah, I like the low drag look

Thanks

[dusterdude]

not sure about the 400,but, late 80`s to late 90`s cbr 600 arm is a fairly easy swap on a 750 and will give 3-4 inches extra length.

[754]

If interested I can run you through the short course of extending, yours. A little bit of machining, some welding.. nice appearance for very little effort. Can be even a lot less work if you are running struts.

[turboguzzi]

dont worry too much about about width as any above 400cc sohc will be wider and you'll have to turn new spacers anyway. Make sure to measure the wheel centering against any frame tubes so you can go back to that position with your new s'arm

Drag look is OK if that's what you like but I think that the narrow tire of a 400 will look a bit lost all alone back there... if you go for a wider wheel too, make sure to get the chain pull right.

TG

[Pwfyrcat1]

754,

Would like to hear what you would do? I have access to a welder, and have been practicing a bit myself.  Handy trade.

[754]

I stretched my 750 arm 6 inches for the drags, but run it on the street.

Quick and dirty, I made a tube to same specs as the front portion of swingarm that holds the bushings..except I was running struts. So now I only needed alum spacers to fit tube and swingarm pivot shaft (maybe sleeve as well). To run a working swingarm you will have to fit bronze or oillite bushings and your sleeve & size appropriately

Then figure out stretch and using spacers tack the new tube lined up with the sides of the original to the spacers and original arm.. finish off you welding &gusset if needed. A trick to maintain allignment, bore 2 straps (t) to pivot bolt size and use them to get your offset distance and side alignment.. simply bolt together with spacers then tack and weld.

Using your stock arm has many advantages, everything fits, and it looks like it belongs.  You will however need longer shocks or build relocate your mounts..also longer brake rod. Keeps that stock look though  at first glance.

[Pwfyrcat1]

754,

Do you have pics?  Thx

[754]

Search Bonneville look for a thread that has Bonneville and 754 in the title.. shows a view of how it sits and looks but not the arm off the bike. You can almost see the  original front edge of the swingarm in the pic.


Basically just a long tube parallel to the arm and 2 tubes connecting them...pretty simple.. used stock brake arm, chainguard, wheel bolts right on.. just deal with shock length or mounts.