$2 front mount fix for cruiser frames
- Thread starter joek
- Start date
i tried a rancho suspension urethane swaybar mount.
complete waste of money. looked cool, but if the motor's not mounted solid to the frame, it's gonna move. and when it moves, it's gonna break studs, or worse.
the myth that a rubber mounted engine reduces vibrations, is just that, a myth. it actually isolates all the vibration to the engine itself, and will shake it all loose.
a solidly built bike, good tires, grips, and pedals will take care of vibrations with a solid mounted motor.
complete waste of money. looked cool, but if the motor's not mounted solid to the frame, it's gonna move. and when it moves, it's gonna break studs, or worse.
the myth that a rubber mounted engine reduces vibrations, is just that, a myth. it actually isolates all the vibration to the engine itself, and will shake it all loose.
a solidly built bike, good tires, grips, and pedals will take care of vibrations with a solid mounted motor.
Go ride a Panhead, Shovelhead, or Ironhead Sportster Harley-Davidson, my friend. You will change your mind on that one.
I have - and I haven't changed my mind.
There's a world of difference between those ol' motorcycles and our retrofitted bicycles. The cheap castings, cheesy hardware, and only two low points of contact being the biggest issues. In addition - many of the vintage HDs were hard mounted anyway, and HD forums are filled with this same dispute lol
Harley motor mounts (granted they're billet, but the point's the same);
HT motor mount;
A slightly different story methinks
Like bairdco said - rubber mounts isolate vibration - they don't "eliminate" it, so if alla shakin' is isolated to the engine only in the interest of your comfort - your mounting hardware will pay the price. It really is better to jus' get a comfy seat and grips.
There's a world of difference between those ol' motorcycles and our retrofitted bicycles. The cheap castings, cheesy hardware, and only two low points of contact being the biggest issues. In addition - many of the vintage HDs were hard mounted anyway, and HD forums are filled with this same dispute lol
Harley motor mounts (granted they're billet, but the point's the same);
HT motor mount;
A slightly different story methinks
Like bairdco said - rubber mounts isolate vibration - they don't "eliminate" it, so if alla shakin' is isolated to the engine only in the interest of your comfort - your mounting hardware will pay the price. It really is better to jus' get a comfy seat and grips.
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great idea, that''s really, top notch. I have never bought a hockey puck but this truly is a creative idea for many applications. Thanks for sharing.
What I meant was that those old motorcycles with thier rigid mounted egines tend to rattle ALL the bolts loose on the whole bike.
if i had an old shovelhead, pan, or knuckle, i probably wouldn't give a rat's a$$ if anyone's chinese toy motor came loose on their chinese toy bicycle...
You are scary. Have you ever had or made some business with engines mounted the rubber way before? Yes ....No? Most motor cycle engines since the late 40's are mounted that way, in rubber. And these china engines could almost not be compared to them.if i had an old shovelhead, pan, or knuckle, i probably wouldn't give a rat's a$$ if anyone's chinese toy motor came loose on their chinese toy bicycle...
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There are many engines mounted on rubber to isolate vibration. Rubber mounting is very common on marine engines, snowmobile engines, almost all aircraft engines, stationary engines powering pumps and generators and many others. Mounting an engine on isolators does not increase the vibration of the engine itself but protects the structure the engine is mounted on. Low speed engines tend to sit on softer mounts to reduce the low frequency vibes while fast revving (most two strokes) can be mounted on harder rubber mounts because the vibration is almost all high frequency stuff. Isolating the vibes will reduce wear in all joints and fasteners on the structure. Fretting of mating surfaces will also be reduced. The engine itself will not experience any practical increase in vibration during it's operation and won't have any more damage or loosening of fasteners than if it were hard mounted. Most likely less since a lot of the vibration will be absorbed in the rubber mount rather than being echoed back in a hard mount. There's no reason that a solidly mounted engine will move in the mounts as long as they are tight. In normal operation these motorized bikes only put a rear pulling load on the engine, not as sideways load. Also the load is almost perpendicular to the rear mounting which also reduces the tendency of the engine to shift under load. The V shape of the mounting will also help reduce tendencies of the engine to move sideways due to vibration. Using a hard rubber like that of a puck will also help prevent movement. With the increased vibration on the mounting brackets of a metal to metal mounting I'd bet there's about an equal chance of engine movement compared to a well mounted engine on rubber isolators.
Brilliant post I must admit - but there a few things I must dispute. All of the aforementioned engines are designed with various densities of "soft" mount in mind - not limited to but including far batter fasteners, more of them, and strategically placed. Of course soft mounts won't increase vibration (not sure where you got that) but it does isolate the engine's vibration - putting all the stress on just the fasteners rather than diffusing it through the entire frame via the mount itself.
The hockey puck mod is not a bad one by any means - the primary mount being the rear one, the front mostly preventing lateral movement. Harder compositions like urethane (and the puck) aren't as prone to the mount sheer problems (may not actually suffer from them at all) but what gets tricky is when people freely misuse the word "rubber" as soft mounting one of these engines is a recipe for disaster, it's just a matter of time.
The hockey puck mod is not a bad one by any means - the primary mount being the rear one, the front mostly preventing lateral movement. Harder compositions like urethane (and the puck) aren't as prone to the mount sheer problems (may not actually suffer from them at all) but what gets tricky is when people freely misuse the word "rubber" as soft mounting one of these engines is a recipe for disaster, it's just a matter of time.
Great setup, I think I may be going with this mount. I would like to request to see if you have or can you get me a picture from the bottom and the top. Thanks!made it this morning out of a $2 hockey-puck and the stock mount in the BGF kit. engine is aligned and rock solid. FWIW Joe
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It does not show well in the photo, but the steel adapter plate in the photo is modified. put it in a large vise and used a BFH and a block of wood to bend it lengthwise to match the angle of the down tube.
The best thing about this set up is that the u bolt won't interfere with the muffler like others do. good job.
i tried using a couple different types of rubber when first building the bike, when i finally picked what i wanted to use it ran great for awhile but i eventually broke my mounting hardwear for the rear. so after i took it all apart fixed everything and remounted using nothing but solid mounting i have noticed there a little vibration, but not enouhg to fuss over i had more vibration using rubber in the mounts since i have gone metal to metal for mounting i havent had a single proble, the mounts are rock solid and are doing great.
Note that i do take my bike of road and through trails which can cause more bouncing around than the road, and i am also still rocking mt bike tires for the traction in the trails.
I like the hockey puck idea, and am not knocking it in the least bit, it is creative and cheap which is always very helpfull. I will be interested to hear how it works over a period of time.
Note that i do take my bike of road and through trails which can cause more bouncing around than the road, and i am also still rocking mt bike tires for the traction in the trails.
I like the hockey puck idea, and am not knocking it in the least bit, it is creative and cheap which is always very helpfull. I will be interested to hear how it works over a period of time.
yup
idk if you cna see it. but i used that paltte wiht my BGF kit as well. was the only way it would mount up in my 4500
p.s. i didnt use a ubot ( yet) on mine, i drilled through the frame with an ace hardware bolt 3", and nut/washer. it vibes, yes, I will try this though before too long, but in east tn. not much of a market for hockeypucks though. will check ebay, and the classifies here as well
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EXCELLENT and looks great too>I've always used the appropriate sized muffler clamp with the oversize plate (mount holes already drilled) welded onto the nut side. Your method adds the finishing touch. That is bullet proof!
Need It Make It Got It
That is a great solution to a common problem! And all the money saved can go into the build
That is a great solution to a common problem! And all the money saved can go into the build