Author Topic: pavement racers.  (Read 2832 times)

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Offline debgeo

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pavement racers.
« on: December 14, 2010, 01:00:14 AM »
On motorcycles running on pavement is everybody running suspension front and back.I know some run rigid rear suspension at Salt Flats. Would like feedback relating to pros and cons. As always THANKS
George---Sidecar in progress

Offline bak189

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Re: pavement racers.
« Reply #1 on: December 14, 2010, 09:46:48 AM »
I note "sidecar in progress"  ......are you talking about the suspension on a LSR sidecar?????
If you are ......limit the suspension.....are you planning on ballast or a passenger????.......If it is a solo bike forget my post.......I will leave that to others......
Question authority.....always

Offline Seldom Seen Slim

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Re: pavement racers.
« Reply #2 on: December 14, 2010, 10:18:25 AM »
I've never been on a solid-rear bike on the salt -- but would strongly recommend suspension back there.  There's enough bumpiness to make the rear wheel bounce, even if only a little, and you want maximum traction - not wheel in the air -- at all times.  Rebound compression low, damping high. 
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Offline oz

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Re: pavement racers.
« Reply #3 on: December 14, 2010, 12:19:35 PM »
I run rigid with no problems although I aint pushin out huge HP I do get a bit of spin up but it seems to get the power down ok
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Offline RidgeRunner

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Re: pavement racers.
« Reply #4 on: December 14, 2010, 12:24:22 PM »
Ran struts on the salt in '71, about shook my kidneys out.

Went back to a much smoother salt in '72 with shocks, MIGHT have snuck by with the struts with the better conditions but shocks sure made for a much better ride.

From what I have seen:  I'll never try a bike at Maxton with out supension on rear even though I've seen ridgeds there.  Loring is much smoother but anything I get going to run there would have some suspension on the rear.

Haven't seen any other LSR venues yet so can't offer valid coments on them.

Mileage for those with a younger body may vary  :wink:

                             Ed

Offline dr j

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Re: pavement racers.
« Reply #5 on: December 14, 2010, 01:02:37 PM »
My 1st meet for my Honda 250 in May 2008 at Maxton Mile I ran rigid rear to a then record of 101mph or so.  It was a new build and in shoving the 4stroke 250 engine into 2 stroke 125 chassis the carb went where the front mount for the rear shock was.  So cut out the mount and reweld further back but could not find a short enough shock quickly, so rigid strut it was.  Every run down the track I knew the rear tire was off the ground in about 3 places (including in one of the David Whealon Photos).  Not unstable but not pleasant either.  Made me think about when the bumps were coming rather than counting shifts and concentrating on my tuck.  It was the first thing I fixed before my next meet.  So I would suggest not designing something to be rigid, but if there are no alternatives it can be run at least at the 100mph range.  I hope this helps.
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Offline gearheadeh

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Re: pavement racers.
« Reply #6 on: December 14, 2010, 04:12:05 PM »
Many a year ago (common for me) I raced a rigid bike at the drag strip. I just replaced the 2 coil over shocks with struts. It was fine at the track, but once while driving to the track was a near accident. As I was coming around the corner onto the freeway I hit a bump. A bad combination of leaning and hitting a bump with no rear suspension. The back of the got kicked around so far I was near sideways. I would just hope that the turn around at the end of the track is smooth!
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Offline 55chevr

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Re: pavement racers.
« Reply #7 on: December 14, 2010, 05:35:33 PM »
I have raced a rigid frame at Bonneville, Maxton and Loring ... You definitely are aware of no rear suspension but it is not a cause for concern ... at least at the speeds I ran ... 150 mph ... the worst is the return road which actually hurts.

Offline fastman614

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Re: pavement racers.
« Reply #8 on: February 06, 2011, 12:16:36 AM »
We ran turbo'd lots of bikes in the 70s at Bonneville... The first Honda- stock framed with a turbo setup of our own design on it, got into the high 170s, the long  dragster style framedHonda got to about 185 and change.. (no boost control and we kept stretching head studs) ... later on the stock framed turbo'd Kawasaki KZ1000 went over 181 one way.... they were all rigid or made rigid or mlike we set recoy b is the onade rigid by using struts.... The Kawasaki rsd with and got to more or less properly shake down.... we remain of the belief that we had about 40 MPH of tire spin and that shocks and some extra ballast would have gotten us over 200MPH a way back then....

IMO.... go for suspension if you can.... (just don't ask me why our lakester doesn't have any ..... but at virtually zero tire slip, it does not seem to be a problem-yet)
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