MRP Motorsport Community
MRP Home Birel America Go Rotax KartingBiz Register FAQ Members List Social Groups Calendar Search Today's Posts Mark Forums Read

Go Back   MRP Motorsport Community > Technical Support Forums & Discussion > Baseline Set-Ups for Birel & Monza

Reply
 
Thread Tools Display Modes
Old 03-24-2009, 07:48 AM   #1
Marc Miller
Birel & Rotax Specialist
 
Join Date: Jan 2008
Posts: 850
Exclamation C28

Baseline set-up information for Birel C28
__________________
Marc Miller
Director of Brand Development
MRP Motorsport/Birel
Marc Miller is offline   Reply With Quote
Old 03-24-2009, 11:01 AM   #2
Marc Miller
Birel & Rotax Specialist
 
Join Date: Jan 2008
Posts: 850
Default

Hello everyone,

Below you will find baseline set-up information for the most popular junior karting chassis in North America, the Birel C28.

Our suggestions:
- Tie-rods: mount the tie rod ends underneath the spindle arms, not above.
- Remove front bar

Front width: Start with 2 thick spacers on inside of wheel
Front wheels: Douglas 4.75" spun aluminum bearing mount wheels

Seat measurements for standard Tillett Cut Down seat:
48cm (from front bar heal area to left lip of seat)
48.5cm (from front bar heal area to right lip of seat)
22cm from axle to top of seat (from very top)

Rear Axle: 1040mm F axle
Rear hubs: standard gold 30mmx35mm Freeline hubs
Rear width: start with 46.5" (inches) using Douglas 5x5.5" spun aluminum wheels

You can widen the rear of the kart to help free it up based on track conditions.
__________________
Marc Miller
Director of Brand Development
MRP Motorsport/Birel
Marc Miller is offline   Reply With Quote
Old 07-05-2010, 04:12 PM   #3
davidkakb
Rookie
 
Join Date: Dec 2008
Location: Cleveland, Ohio
Posts: 2
Default

I purchased a used Birel C28 and their setup was similar only they were using a B axle instead of the F you post here. Can you give me some more info on what the tradeoffs are for using one vs. the other? Thanks, David
davidkakb is offline   Reply With Quote
Old 09-20-2010, 04:19 PM   #4
Edward louis
Rookie
 
Join Date: Oct 2009
Posts: 11
Default

we use the F earlier in the yr when grip and track temps are down. then switch to the B
Edward louis is offline   Reply With Quote
Old 09-29-2010, 01:00 PM   #5
Marc Miller
Birel & Rotax Specialist
 
Join Date: Jan 2008
Posts: 850
Default

Hi Edward -

Just for everyone's reference, our national team rarely uses the B axle even when the track rubbers up. It is certainly an option, but going too soft may bind up the chassis. Just adding to this for reference.
__________________
Marc Miller
Director of Brand Development
MRP Motorsport/Birel
Marc Miller is offline   Reply With Quote
Old 12-14-2010, 10:54 AM   #6
TCowen
Rookie
 
Join Date: Dec 2010
Posts: 1
Default

What rear percentages are ideal? We are running the Yamaha Rookie Sportsman in Daytona and on the 950mm with no weight it scales out at 55% rear and the weight is right on the money. Don't want to move the seat if we don't need to as he is comfortable as he is. Is this too much rear %?
TCowen is offline   Reply With Quote
Old 04-04-2011, 03:38 PM   #7
kart95
Rookie
 
Join Date: Oct 2010
Posts: 4
Default Is the baseline differnt for a Micro vs. Mini

I'm wonding if the chassis setup should be different for a micro vs. mini Rotax and the c28 chassis?

Also, can anyone comment on the rear height adjustment baseline starting point?
kart95 is offline   Reply With Quote
Old 04-12-2011, 02:57 PM   #8
Marc Miller
Birel & Rotax Specialist
 
Join Date: Jan 2008
Posts: 850
Default

Quote:
Originally Posted by TCowen View Post
What rear percentages are ideal? We are running the Yamaha Rookie Sportsman in Daytona and on the 950mm with no weight it scales out at 55% rear and the weight is right on the money. Don't want to move the seat if we don't need to as he is comfortable as he is. Is this too much rear %?
We don't scare the karts - so try it this way and report back to how it goes. Good luck!
__________________
Marc Miller
Director of Brand Development
MRP Motorsport/Birel
Marc Miller is offline   Reply With Quote
Old 04-12-2011, 02:58 PM   #9
Marc Miller
Birel & Rotax Specialist
 
Join Date: Jan 2008
Posts: 850
Default

Quote:
Originally Posted by kart95 View Post
I'm wonding if the chassis setup should be different for a micro vs. mini Rotax and the c28 chassis?

Also, can anyone comment on the rear height adjustment baseline starting point?
Typically not, though with the higher HP of the Micro, you may need more grip so castor/camber may come more into play.
__________________
Marc Miller
Director of Brand Development
MRP Motorsport/Birel
Marc Miller is offline   Reply With Quote
Old 10-20-2011, 08:53 PM   #10
bill berzabek
Rookie
 
Join Date: Oct 2011
Posts: 1
Default axle length C28z

I was wondering what affect a shorter or longer axle will have on handling. Instead of the base 1040mm axle what affect would a 1000mm axle have or 1060mm axle have.

Thanks in advance.

Last edited by bill berzabek; 10-20-2011 at 08:54 PM.
bill berzabek is offline   Reply With Quote
Old 10-21-2011, 12:01 PM   #11
Chris Lobaugh
Birel Specialist / Engineer
 
Join Date: Jan 2008
Posts: 237
Default

A longer axle creates more side bite or "grip". Conversely a shorter axle has less side bite and helps "free" the rear of the kart up.
__________________
Chris Lobaugh
Birel Engineer & Specialist
chris@mrpmotorsport.com
Chris Lobaugh is offline   Reply With Quote
Old 11-11-2011, 01:26 PM   #12
J-Dubya
Rookie
 
Join Date: Nov 2011
Posts: 2
Default new to karting

My boy has a c28 with a Gazelle, we are totally new, and have just begun to try yo wrap my head around chassis setup. I have heard read conflicting advice, so I am very pleased to find this resource.

First, can you recommend a good book or reading to learn about chassis setup particulary for the cadet racer?

My boy is on the small side 51" 52#'s. First of all we are looking to get a good seat setup. Is the baseline setup good for a smaller kid (has Noonan pedal platform setup)? With a smaller lighter kid, would it be advantageous to munt the seat incrementally higher? Ar e there other departures or directions from the baseline setup that should be considered for a smaller kid?

Is axle hardness/softness a function only of track conditions or does the driver size factor into the setup?

One guy was mentioning that I might want to munt balast high to help with weight tranfer -- is this the right thinking?

I am confused by axle width, the comment in the post above says width increases grip, but I have heard and read that a wider axle promotes oversteer. Is this a function of entry or exit?...

Thanks,
jw
J-Dubya is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -5. The time now is 07:45 PM.

Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2018, Jelsoft Enterprises Ltd.
Copyright 2008 - MRP Motorsport - All rights reserved