Landracing Forum Home
October 21, 2017, 12:28:28 PM *
Welcome, Guest. Please login or register.
Did you miss your activation email?

Login with username, password and session length
News:
BACK TO LANDRACING.COM HOMEPAGE
 
   Home   Help Search Calendar Login Register  


(Note: Donations are not tax deductible)







Live Audio Streaming and Archives of Past Events
Next Live Event: TBD
Pages: [1]   Go Down
  Print  
Author Topic: Push start for a Streamliner question,  (Read 2556 times)
0 Members and 1 Guest are viewing this topic.
baron
Jr. Member
**
Offline Offline

Age: 52
Location: Saugerties, NY
Posts: 35




Ignore
« on: February 16, 2016, 09:55:58 PM »

Hi Folks,

I am currently designing a 125cc powered streamliner. Like most streamliners we will require help getting started due to the tall gearing especially with the tiny clutch of a 125cc two stroke motor and the serious lack of torque; As we know the rules allow for a push start and this is a simple method of dealing with the tall gearing problem but it seems a bit clumsy. Many have pulled this off no problem so maybe its the way to go. Another option is an additional transmission acting as an under drive turning your 6 speed  transmission into a seven speed. Much like Sam Wheeler's effort for example, but this is my least favorite solution as it involves too much money but his solution is all class.
-A third option came to mind and herein lies my question; can we run a small electric motor that engages the chain and propels the bike for the first .25 of a mile? (This is the distance stipulated in section 2. R. in the AMA rules)  The motor would disengage automatically at its peak RPM which correlates to 40mph or so and happens within the first .25 of a mile.
Thoughts?

Cheers,
Scott
Logged
donpearsall
Sr. Member
****
Offline Offline

Age: 65
Location: Spokane, Washington
Posts: 658



WWW

Ignore
« Reply #1 on: February 16, 2016, 11:07:34 PM »

I hope Drew will chime in as he is the AMA/FIM steward. But my first impression as a non-tech participant is that you would have to convince techs that the electric starter motor cannot possibly assist the gas engine. Otherwise you are in the multiple engine category.  That may be hard because they both would drive the rear wheel. Do you have some sort of engagement that ensures this?

Don
Logged

550 hp 2003 Suzuki Hayabusa Land Speed Racer
Eddieschopshop
Full Member
***
Offline Offline

Location: Sacramento, California
Posts: 144




Ignore
« Reply #2 on: February 16, 2016, 11:25:44 PM »

Even if it disengages at slow speed (and could be proved) it is an additional motor/power source in the car.  Sounds like a clear no to me. 
Logged
RichFox
Hero Member
*****
Offline Offline

Location: San Mateo, Ca
Posts: 2418





Ignore
« Reply #3 on: February 17, 2016, 12:04:45 AM »

Remember the KISS rule. Push starts are simple.
Logged
baron
Jr. Member
**
Offline Offline

Age: 52
Location: Saugerties, NY
Posts: 35




Ignore
« Reply #4 on: February 17, 2016, 12:29:02 PM »

Even if it disengages at slow speed (and could be proved) it is an additional motor/power source in the car.  Sounds like a clear no to me. 

Sounded like a clear no to me as well but when i deferred to the rule book there seemed to be no mention of it. The whole thing rubs me the wrong way but, as i am sure you know, all ideas and rules must be explored as they sometimes takes you places you hadn't thought of.
Remember the KISS rule. Push starts are simple.
KISS is our mantra but the push start makes things difficult with our testing scenario.

My emails to Drew kept getting bounced back so i thought i would post it here.

Cheers,
Scott
Logged
bbarn
Sr. Member
****
Offline Offline

Age: 47
Location: Harmony, PA
Posts: 614





Ignore
« Reply #5 on: February 17, 2016, 01:25:33 PM »

How good is your starter? What does it look like? How is it built? You aren't charged a second motor penalty for a starter motor. Perhaps you can get creative there and drive yourself into first gear with a starter....

This is starting to get into the area of my idea of for an awesome push vehicle. The rule book doesn't say they can't have the JATO unit on the push vehicle, it only says the competition vehicle has to be wheel driven.

Who's up for a 300mph push?  LOL

I can hear the question now "Why do you have chutes on your push vehicle?"

Seriously, even for testing in remote areas unless you are by yourself a push vehicle is the most straight-forward way to go. If there were a better way you'd probably already see people doing it at B'ville or Elmo.
« Last Edit: February 17, 2016, 01:28:53 PM by bbarn » Logged

I almost never wake up cranky, I usually just let her sleep in.
saltracer1
Full Member
***
Offline Offline

Age: 66
Location: Lafayette, La.
Posts: 147





Ignore
« Reply #6 on: February 17, 2016, 07:00:30 PM »

just a side note we were behind some motorcycle streamliner guys one year that were using a cable to pull the bike up to speed. Well, the cable did not let go when hoped and the bike went flopping around like a fish. Needless to say when the driver exited the bike he was pretty pissed!
Logged
Old Scrambler
Sr. Member
****
Offline Offline

Age: 70
Location: Plymouth, WI
Posts: 629


Going Fast - Slowly




Ignore
« Reply #7 on: February 17, 2016, 09:21:20 PM »

In '09 I was a spectator but soon saw an opportunity to help a few competitors. I helped to push-start a 150cc streamliner...............I was given instructions about a safe-place to push on the body.........and off we went........maybe into the low teens.  I now ride a 250cc pushrod 4-stroke bike............and often get a little push to get me rolling.
Logged

2011 AMA Record - 250cc M-PG TRIUMPH Tiger Cub - 82.5 mph
2013 AMA Record - 250cc MPS-PG TRIUMPH Tiger Cub - 88.7 mph
2016 AMA Record - 750cc M-CG HONDA CB750 sohc - 130.7 mph
2016 AMA Record - 750cc MPS-CG HONDA CB750 sohc - 137.7 mph
Chasis Builder / Tuner: Dave Murre
baron
Jr. Member
**
Offline Offline

Age: 52
Location: Saugerties, NY
Posts: 35




Ignore
« Reply #8 on: February 19, 2016, 01:03:32 PM »

Thanks for the thoughts and suggestions folks.
Now back to work or I'll have no streamliner to push. grin

Cheers,
Scott
Logged
Pages: [1]   Go Up
  Print  
 
Jump to:  

Powered by MySQL Powered by PHP Powered by SMF 1.1.21 | SMF © 2015, Simple Machines
Simple Audio Video Embedder
Valid XHTML 1.0! Valid CSS!


Google visited last this page July 24, 2017, 09:18:30 AM