Broke My Frame!

I'm wondering if it would be a good idea to "break" the sharp edges of the motor mount with a file. I'm thinking the sharp edge may have sawed through the tube.
 
I'm wondering if it would be a good idea to "break" the sharp edges of the motor mount with a file. I'm thinking the sharp edge may have sawed through the tube.

I don't think this would help in most cases. These engines literally do vibrate enough to cause repetitive stress fracturing in metal. It's just like bending a paper clip. You can do it only so many times until the metal becomes soft then eventually just breaks apart.
I don't think the mounts are the problem I think its the fact that for the most part these engines aren't engineered or manufactured correctly leading to excessive vibrations that eventually destroy the motor or the bike its on.
Happytime mounts seem to have more surface area on the frame than Staton or GEBE mounts but you don't see those motors vibrating frames apart. Personally I think everybody should steer clear of these engines until they're made to some respectable standard, otherwise the HT dealers have no reason to improve their products. Riding a MAB is dangerous enough without having to worry about fuel leaks, bolts vibrating off, broken spokes from half arsed sprocket mounting techniques or the infamous HT seize n' lock that sends your bike into an uncontrollable skid when your engine instantly locks and has no freewheel as a safety measure.
May the buyer beware, these things are bad news.
 
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A track frame or bike is designed for fixed gear or single gear riding, very tight geometry, no gears involved and if fixed,NO BRAKES. Most can be seen at the velodrome in the Olympics or in most major cities ridden by bike messengers. tried a Surly Steam Roller for this build and you know the result; I also ride a Steel-Wool single gear (no motor) designed here in Canada;) most fast!!
Cheers
 
I was hoping you wouldn't say that. I don't know of any track frames designed for "Extreme Forces". A Surly Steam Roller I wouldn't go jumping off anything other than a curb and that's without a motor. Track bikes are meant to be light, not take a beating and the HTs are good for beating the frames (hence why tell people not to drill their frames to mount them). The Surly Karate Monkey would have been a better choice if you are looking to use 700c rims. Of the Surlys I think the Instigator would be the best frame for MB use.
 
Cro-Moly + HT = :(

Cro-Moly is very hard and brittle. I can't absorb energy, its just shears off. Mild steel is softer and can absorb energy. As an example, race used to use Cro-Moly in their roll cages. But it would brake rather than bend. Now its banned in roll cages.
The best and only mat'l people should use with HT's is mild steel. Match cheap with cheap.
Happy riding on your high dollar MB!
 
Another reason why I average 20mph on my bike. Can you imagine doing 35-40mph and having a frame failure or brake failure? Yes, I've had brake pads vibrate loose. Also had steering vibrate lose-handlebar didn't turn the wheel fully--but I was able to catch that when pedalling that i had sloppyh steering.
 
Thats nothing...I had one break a down tube and seat tube all at once! Only thing holding her together was the tube between my legs!

Trek chromoly mountain bike.

yeehaaaw!
 
Cro-Moly is very hard and brittle. I can't absorb energy, its just shears off. Mild steel is softer and can absorb energy. As an example, race used to use Cro-Moly in their roll cages. But it would brake rather than bend. Now its banned in roll cages.

Nope.
SCORE International Off-Road Racing
National Hot Rod Assoc
Sports Car Club of America (big pdf file)
They all want chromoly.

Couldn't find NASCAR's rule book online, but net searching roll cages and NASCAR turns up Chromoly quite often.
 
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