Swing arm angle
Swing arm angle
(OP)
Hi there
Can anyone help What effects on the bikes handling/traction does the change in Swing arm angle have
Kind regards
Stephen
Can anyone help What effects on the bikes handling/traction does the change in Swing arm angle have
Kind regards
Stephen
RE: Swing arm angle
Regards,
MB
RE: Swing arm angle
The wheel base effectively gets shorter, So the wieght would I assume tend towards the rear and the front would lift
If I made the link arm shorter,( altering the swingarm angle) assume this would have the effect of making the wheelbase/swingarm shorter and make the front tend to come up more
Stephen
RE: Swing arm angle
All this being said unfortunatly some 12 year old with his brains in the tool box will get on it and go faster anyway.
Regards,
MB
RE: Swing arm angle
I an trying to reduce the spring preload as much as possible while using the softest spring I can get away with
If I shorten the Linkage arm ( NOT) the swingarm ,,the swingarm altitude changes from -4.3 to -6.9 I dont know what effects this swing arm angle change will produce .. ( I drew the bike on Cad then ran it through the motions and hence noted the wheel base change ) ]
Other than that I would like to know more about the effects the swing arm angle change produces
Stephen
RE: Swing arm angle
I didnt correctly read your comment with regards to the change in swing arm angle.
You have to look at the situations where power is applied and the position of the suspension at that time. Commonly when you apply power the chain pull moment will attempt to cause the bike to rise on its rear suspension (top out), or another way of thinking is the wheel will push itself into the ground. This is opposed by the wight transfer to the rear under accelleration (pitch). The engineers will try to optimise the position of the swing arm pivot to the countershaft to achive a good balace between the chain pull moment & pitch for best comfort, control & traction. You will find that the bike will sit at a position of 30%-50% of available travel when under accelleration. The change in angle thus length will be a minimal factor in traction.
Hope this helps.
MB
RE: Swing arm angle
Regards,
MB
RE: Swing arm angle
That was a very good answer So, if under accel ( throttle pinned ) I am about 30 to 50 % of aval wheel travel
Then with that set up I can have a look at the rising rate ,,,My local track is tight and twisty with only 2 big jumps with a g out before both ,,
So may need more of a rising rate will have a play and see
Stephen
RE: Swing arm angle
Regards
MB
RE: Swing arm angle
Good luck with the suspension settup, I'll try and avoid giving you advice. As mburgess said it can be a pandora's box.
RE: Swing arm angle
go to Tony foales Web site and download the users manual PDf the software itself was very cheap
I am an Engineer and can work all this stuff out from first principles ..but I am flat out...and this software and the help from MB has saved me lots of time...and as a result I have been able to test and make changes on the computer ( I use acad as well) ..then I machine /change the bike ..so far this has given me a resonable machine in a very short time
An example would have been Spring rates ...Stock is 4,2 kg/mm I need 5.4 at 17mm preload ...( have another spring so may go harder based on fresh evidence ,,thanks MB ) that was done on T/F software ,,,I cut the spring to the required stiffness ,,,,( havent tested the spring yet maybe in the weekend if I get a chance )
in conclusion worth the money .... ( the only prob is understanding what the changes do and the effects are ....for which the book is needed
Stephen
RE: Swing arm angle
htt
They have some excel templates for working out spring & leverage charts.
Regards,
MB