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Old 10-27-2010, 12:33 PM
David D.'s Avatar
David D. David D. is offline
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Location: California
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Default Re: Mount bet

Yea that one looks good, guessing a hockey puck is relativly stiff, but would certainly help isolate the high frequency vibrations.... what do they cost?
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Old 10-27-2010, 02:10 PM
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2door 2door is offline
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Default Re: Mount bet

The compound that a hockey puck is made from is hard enough to keep things from moving. I use a very hard urethane bushing in my front mounts too. The material composition is so hard that you can't compress it or even make a mark in it with a screwdriver. This is the difference between rubber and pucks or urethane bushings. Rubber, or ANY soft material will cause problems. This has been explored and explained here time after time. The reason is that you CAN NOT eliminate the vibrations produced by the engine. All you can do is distribute it. You CAN NOT isolate it to the engine itself because the mounting fasteners are then the link between bike and engine and they can't take the stress. Either the fasteners will eventually fail or the threads in the case will. My bet is that if the hockey puck or my urethane bushings were replaced with metal that the degree of vibrations felt in the bike would be the same. This myth of soft mounting engines to "eliminate vibrations" is my pet peeve, just as cheap bikes are to Bairdco.
I'm inclined to simply post my opinion once then back away and let people do what makes them happy but the problem with that approach is that newbies then will not have the benefit of the facts and will soft mount their engines because the theory sounds right. Then they'll have failures and problems that can be directly linked to the resiliant mounting of the engine. I really hate to see a new guy have problems that keep him from enjoying the hobby and his bike and therefore I will continue to argue this issue with anyone who says that soft mounting a Chinese 2 stroke is the way to go.
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Last edited by 2door; 10-27-2010 at 02:20 PM.
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Old 10-27-2010, 03:04 PM
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azbill azbill is offline
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Join Date: May 2008
Location: Fountain Hills, Arizona
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Default Re: Mount bet

I agree fully with Tom (2door) on this
all broken stud probs I have ever seen/had were due to flex at the mounting points

Intelligence is learning from your own mistakes,
Wisdom is learning from the mistakes of others

EZ Motorbike Dealer - Fountain Hills, AZ
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Old 10-27-2010, 03:08 PM
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biknut biknut is offline
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Default Re: Mount bet

I'm a big fan of urethane bushings. My Sportster came with soft rubber bushings that mount the handle bars. They make the handle bars flop all around, and are really nasty. I replaced them with hard urethane bushings made for that purpose. Even though they're very hard in comparison, they dampen vibration about as good as the soft stock ones.

If I could find a hockey puck made out of urethane I think it would work even better than the rubber one I'm using.

I've never made a solid mount China Girl, but my Sportster in solid mount. There's no question it vibrates 10x worse than a China Girl. Sportsters are world renown for having parts break off and roll down the street behind them. After 47 years of production the motor company decided to rubber mount Sportster motors. I've ridden both and to tell the truth I didn't feel much difference either.

Rubber mount or solid mount, everything breaks in time. You know what they say, if it's got tits or wheels it'll give you trouble.
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