seaball

iTrader: (9)

any chance of finding a link for that?

i have great interest in almost anything that comes from mr. stranahan.

Ozwald Bates

Unfortunately I didn't save the thread, I wish I would have. I do believe Mr. Stranahan saved it, and at one time was emailing the entire thread to anyone who need the info. You might try his email address : [email protected] and see if he still has the thread.

I know he went into a pretty deep discussion about the whole arm sweep thing, and I probably explained it totally wrong

Tom

you can adjust arm sweep on the corally Assassin,

basicly, you are angling the inner and outer hinge pins but leaving the wheels pointing straight, so in a set up station your front toe will read zero. Its like kick-up & antidive but on a different plane.

David Joor

iTrader: (1)

RobK has this correct. Ashpalt you can run this but in carpet it is tough on the mind trying to control all the responsiveness.

Randy Cook

iTrader: (1)

David,,,,you got mail. please check your pm's. Thanks

John Stranahan

iTrader: (27)

I just found this thread, I thought I would post my thougts.

When you angle the front drive axle back, it affects the way the outdrive interacts with the dogbone and causes the tire to lift. This holds the front end down in mod and creates stability. In stock this has the effect of reducing front traction for acceleration which is more important in my opinion. I removed the front angle from my Losi as has become the norm now, to have drive axles more perpendicular to the car for lower friction and more front traction for acceleration in stock.

I believe the A-arms were swept back on the Losi during prototype testing to reduce front end chatter on acceleration in Mod. Unfortunately it has this undesirable effect on front traction.

When the rear drive axles are swept forward this drives the tire into the road and creates more rear traction for acceleration at the expense of some small increase in driveline friction. No big drawbacks here.

i still have the 80 page Losi thread if you want it send me an e-mail. The material in this thread has been condensed corrected and clarified in my book "RC Electric Car Reference"

seaball

iTrader: (9)

is shifting the bones back the primary reason for arm sweep?

what does inboard toe do in the case that your bones are still colinear with the outdrives?

why use the change in toe to shift the axles back? what not just space the arms back?

John Stranahan

iTrader: (27)

Seaball- I think the primary reason to sweep the arms back was the chatter (rapid front wheel hop) problem. Both drive-axle angle and arm angle were changed at once so it might be a combination of both that helped; less bite, and a different vibration pattern for the front suspension when the power was on. Anyway the caster blocks and inner A-arm hinge pivots on the A-arm are slightly thicker than the original car. This might be enough to prevent chatter by itself by stiffening things up just enough. I noticed some of the team drivers started moving their arms forward around the same time I was moving mine forward. They kept the inner toe on the hingepins, I removed my inner toe. I moved my arms forward by making new rear hinge pin blocks for the front suspension that took the toe out of the pins completely. It also widened the front track width to the legal limit and lengthened the car. I liked it a lot better this way. I never got any wheel hop on our high grip indoor asphalt track. It is a lot easier to move the arms forward and keep the toe out of the inner hinge pin. Less fabrication. (Thanks for the nice words above).

Another undesirable effect of sweeping the arms back on the Losi is that you lose some front track width. A race car corners better at the maximum with allowed by the rules as there is less weight transfer the wider the car.