Why Is the Swingarm Mounted to the Transmission and not the Frame?
#1
12-13-2020, 06:53 PM
Why Is the Swingarm Mounted to the Transmission and not the Frame?
Hi, I'm new.
It might seem like a stupid question but I haven't been able to find the answer anywhere.
In the Dyna models the swingarm is mounted directly to the rear transmission. Why did Harley Davidson design it this way?
The older models (FLH, FXR ect) were not mounted this way, nor are the modern bikes that Harley makes such as the Road Kings, Sportsters ect.
It seem like it'd be detrimental for the Dyna since the engine is rubber mounted, which would mean that the swingarm is not solidly attached at any point onto the frame, which I imagine would give it more slop than if mounted to the frame.
It also seems like it would be mechanically weaker since the swingarm is mounted to the transmission which is in turn mounted to the motor, so ultimately the rear wheel is only attached to the bike by a few bolts that hold the transmission to the engine.
Again I don't know, I'm only guessing. Please correct me if I'm wrong anywhere.
Ultimately my question is why did Harley design it this way. What are the advantages, if any to this design?
As an aside why did Harley decide to attach the transmission to the motor in the first place? Why not leave them separate as they were in shovelheads and before.
Any info would be greatly appreciated.
Thanks!
It might seem like a stupid question but I haven't been able to find the answer anywhere.
In the Dyna models the swingarm is mounted directly to the rear transmission. Why did Harley Davidson design it this way?
The older models (FLH, FXR ect) were not mounted this way, nor are the modern bikes that Harley makes such as the Road Kings, Sportsters ect.
It seem like it'd be detrimental for the Dyna since the engine is rubber mounted, which would mean that the swingarm is not solidly attached at any point onto the frame, which I imagine would give it more slop than if mounted to the frame.
It also seems like it would be mechanically weaker since the swingarm is mounted to the transmission which is in turn mounted to the motor, so ultimately the rear wheel is only attached to the bike by a few bolts that hold the transmission to the engine.
Again I don't know, I'm only guessing. Please correct me if I'm wrong anywhere.
Ultimately my question is why did Harley design it this way. What are the advantages, if any to this design?
As an aside why did Harley decide to attach the transmission to the motor in the first place? Why not leave them separate as they were in shovelheads and before.
Any info would be greatly appreciated.
Thanks!
Last edited by d3adrock; 12-13-2020 at 09:20 PM.
Top Answer
12-14-2020, 10:02 AM
Road Warrior
Just a note to all smart-asses, at one time YOU didnt know squat about anything. You learned by asking questions, sometimes those questions were perceived to be dumb, but you asked them anyway. Ya know, motorcycling is dying, HD is teetering on folding because younger folks are not getting into bikes. Maybe instead of being an jerkoff, you could help a new guy. I dont have an answer for him, but its a legit question, Ive wondered myself. Go ahead and dog pile on me- I dont GAF.
#3
12-13-2020, 08:35 PM
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#4
12-13-2020, 08:44 PM
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#5
12-13-2020, 08:48 PM
But wouldn't having the swingarm bolted to the transmission/engine make the whole thing more flixible since now the rubber is allowing some slop/flex between the engine and frame?
#7
12-13-2020, 08:54 PM
Road Warrior
It makes sense that an engine/transmission bolted together would be stiffer (although why not just make the frame stiffer?)
But wouldn't having the swingarm bolted to the transmission/engine make the whole thing more flixible since now the rubber is allowing some slop/flex between the engine and frame?
But wouldn't having the swingarm bolted to the transmission/engine make the whole thing more flixible since now the rubber is allowing some slop/flex between the engine and frame?
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#8
12-13-2020, 08:55 PM
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#9
12-13-2020, 08:59 PM
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#10
12-13-2020, 09:12 PM
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