Gambler mini bike enduo 2020

#1
These are the newly posted classes for Gambler 2020 in Oregon. (100 mile minibike race):

In 1970 I dreamed of being a minibike champ at my Saddleback race. Lol.
Next year I have another chance!!! 50 years. Gonna be an adventure.

Here are the classes:

1) Small Frame
2) Box Stock, governed at 3600 rpm
3) No Suspension
4) Front Suspension
5) Full Suspension
6) Big Block
7) Solo Male
8) Solo Female

I’m going Box Stock or full suspension. Probably Powell

Who else is interested in discussing? Or even participating as a team?

https://7fecc2bb-4ef4-4813-8d24-629...d/190309_df7319bc983b4e7281e52ed30df915b2.pdf
 
#7
any different mods you want to do to the bike before the next race bryan.
Yes I will be adding some kind of anti vibration engine mount the vibrations really took its toll on my hands and arms over the course of the race. And the other big thing will be adding a front break. Other than that just tuning suspension I think I need to stiffen the forks and rear springs. I want to try a flat slide carb. Thicker seat and maybe paint the bike. Keep an eye on my build I will be updating it when I start working on it again
 
#10
...I will be adding some kind of anti vibration engine mount the vibrations really took its toll on my hands and arms over the course of the race...
Rubber mounting the engine can bring up all sorts of problems. Much easier to add rubber bar mounts. Off road motorcycles have used 'em for ages. Parts are inexpensive and easy to get. All you need to do is modify the top triple clamp a bit.

 
#11
What Tom said to do is good advice! You could also use the throttle and grip that OMB sells, part # 424028. They really help out with vibration and well made! Try them, you'll be really happy. Add in a pair of anti-vibration gloves and you can ride all day!
 

delray

Well-Known Member
#12
What Tom said to do is good advice! You could also use the throttle and grip that OMB sells, part # 424028. They really help out with vibration and well made! Try them, you'll be really happy. Add in a pair of anti-vibration gloves and you can ride all day!
I believe some guys call them jackhammer style grips. I run a pair on a race bike that pulls over 7000+ on the straight aways and with good pair gloves. they are a lot more comfortable then the old original kind that most minibikes had.
 

delray

Well-Known Member
#13
i'm with tom. rubber mounting the motor can be the worst thing you can do on a bike for racing.
tom, for the handle bar post mount you said that was rubber? was it the real hard rubber or soft? I wonder if urethane bushing would work good?
 
#14
i'm with tom. rubber mounting the motor can be the worst thing you can do on a bike for racing.
tom, for the handle bar post mount you said that was rubber? was it the real hard rubber or soft? I wonder if urethane bushing would work good?
The rubber cushions on my kid's '02 CR250 are made from fairly soft rubber and allow some movement of the handlebars, but within a very limited range. I believe that aftermarket clamps and cushions are available, but going with harder material seems to defeat the purpose.
 
#15
Rubber mounting the engine can bring up all sorts of problems. Much easier to add rubber bar mounts. Off road motorcycles have used 'em for ages. Parts are inexpensive and easy to get. All you need to do is modify the top triple clamp a bit.

The rubber cushions on my kid's '02 CR250 are made from fairly soft rubber and allow some movement of the handlebars, but within a very limited range. I believe that aftermarket clamps and cushions are available, but going with harder material seems to defeat the purpose.
My Aluminum bike and both of my Hot Shots, And the Bearcat Twisters. All used rubber mounts for the engine. So did most of the Snow mobiles. I have ridden the Aluminum bike over a lot of rough terrain without any problems ?
 

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delray

Well-Known Member
#17
it's not the rough terrain that creates the problem. when running these little clone motors at 7000+ rpm's you really don't want them moving around.
in the case of bryan's bike creating vibrations or having is hands turning numb after hours of riding. I would first look into a good pair of handle bars grips and gloves. I have seen where people also experience vibration from a pair of hard tail front forks. but in bryan's case he is running suspension. so something like tom mention earlier about using rubber on the handle bars is something to look into and try. other problem where he is getting vibration or making is hands go numb could be running the alumimun flywheel and running a clutch that doesn't really balance well at high rpm's
 
#19
My Aluminum bike and both of my Hot Shots, And the Bearcat Twisters. All used rubber mounts for the engine. So did most of the Snow mobiles. I have ridden the Aluminum bike over a lot of rough terrain without any problems ?
Thanks for this post and pic.
Always wanted to build an aluminum frame drag byke but was always worried about vibrations and cracking.
Aluminum is prone to this. It’s likely that the rubber mounting is they key to your frame holding up so well, as well as the design of the frame. Did you design and build it yourself? Very nice job
 

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