Engine Mount Bolt Size?
- Thread starter Moespeeds
- Start date
Moe, did you get them an extra 1/4" longer?
Moespeeds
Well-Known Member
I don't have the stock BD mount Ray, so it's different. I somehow have some debris that fell down inside one of the bolt holes that won't come out with a magnet, I'm going to blow it out Fri when I get some time to work on it. The hole is slightly stripped, the bolt came loose and was allowed to rattle around in there for awile. I'm trying to figure out if it's serious enough to weld and re-tap. I'll sort it all out over the weekend.
Are the threads to damaged to just chase with a tap? Those threads go down in the head a long ways. Seems a longer bolt will help you out also.
Good luck with it,
Ray
Moespeeds
Well-Known Member
The bolt actually milled out the top 70% of the hole, beyond re-tapping or a helicoil. I have about 30% of the threads left down there, I was out hunting for a longer bolt yesterday. The problem is with my coil mount, it didn't fit properly and I never made proper spacers for it, so that's what I get. Like I said, I have the time Fri so I'll get it all straight. If I have to drill deeper into the head, can I?
Moe, I wouldn't drill any deeper. It's goes down in there quite a bit already. I would drill out and install a helicoil first then you can fix it later whenever you may pull the head.
Moespeeds
Well-Known Member
The problem is it milled it out in the shape of a cone. A helicoil won't work, and to drill it out I'd have to go up to about 1/2". I want to see if the bolt will hold at all in the threads that are there, and talk to my buddy to see if he can get a weld in there without taking the head out.
Well surprised you didn't notice it sooner with all the vibration.
Being you have a Chopper you may be able to get someone to do the welding and drilling/tapping while in the frame. You have lots of clearance once you remove the tank.
Good luck,
Ray
Staffy
Active Member
Which mount do you have? Any pic's...have just got my self a Vulcan mount - hope thats not going to have any issues...
Thanks
Moespeeds
Well-Known Member
Here is a pic of how I screwed it up:
See where the mount touches the fins? The mount doesn't perfectly fit, so it needed to be spaced about 1/4" higher. I had no aluminum spacers around, so I used stainless nuts for the job "temporarily". Well we all know how that goes. I started riding, and it was holding fine, but if you look close at the mount on the right, it backed out just a little, but the nut jammed against the coil mount, held the bolt rigid, and was vibrating around in that hole for who knows how long. The front mount held securely, and I didn't notice any unusual vibration.
See where the mount touches the fins? The mount doesn't perfectly fit, so it needed to be spaced about 1/4" higher. I had no aluminum spacers around, so I used stainless nuts for the job "temporarily". Well we all know how that goes. I started riding, and it was holding fine, but if you look close at the mount on the right, it backed out just a little, but the nut jammed against the coil mount, held the bolt rigid, and was vibrating around in that hole for who knows how long. The front mount held securely, and I didn't notice any unusual vibration.
Staffy
Active Member
Ouch....:bang: :bang: I take it you will be replacing the mount or looking to get the spacers...like Ray's idea - makes most sense, "(Being you have a Chopper you may be able to get someone to do the welding and drilling/tapping while in the frame)" now just finding someone in your area that does this. What material is the head - aluminum is guess....if that is the case finding someone who does aluminium welding could be tough...either way the good news is it's "fixable" :up: :up: :up: Good luck.
Moespeeds
Well-Known Member
My buddy has a TIG and should be able to fill it in, it's whether or not it needs to. A few years back I had an engine mount tear out at the track on my race bike. On the advice of a buddy, I filled the hole with some of that steel epoxy shit, drilled it and tapped it right there. I was going to weld it up later, but I never did and it held for 3 seasons! Now a Yamaha R6 is no S&S 117, but it still vibrates like crazy at 15k RPMs. I'm going to give that a try and ride to MD on Sunday. We'll see how it holds, I can always drill it all out later.
Well now you all know why I went with the yankee motor mount, and a vulcan coil mount and coils. HOWEVER, that was not without much modification.
Here's the end mount to the frame.
Once I bolted the motor mount to the heads you can see that it was a 1/2" shy of making the connection
So I had a new piece CNC machined with an offset because I didn't want any stupid spacers.
Then I figured out that the key switch wouldn't fit... as shown
You can see in the vulcan setup they have a creasant milled out of the bottom.
And if I was going to need that milled out... I might as well fix the front leading edge. It was blunt and I didn't like it. So I had the miller take a 45 degree canter off it for that finished touch.
Blunt edge shown below.
So here's the canter off the front
The bottom milled for the key switch
Then I got it all chromed...
But man o man... that cost me some serious COIN. And its just ANOTHER reason why my tag says what it does above my avatar.
But damn it looks good when done RIGHT
Here's the end mount to the frame.
Once I bolted the motor mount to the heads you can see that it was a 1/2" shy of making the connection
So I had a new piece CNC machined with an offset because I didn't want any stupid spacers.
Then I figured out that the key switch wouldn't fit... as shown
You can see in the vulcan setup they have a creasant milled out of the bottom.
And if I was going to need that milled out... I might as well fix the front leading edge. It was blunt and I didn't like it. So I had the miller take a 45 degree canter off it for that finished touch.
Blunt edge shown below.
So here's the canter off the front
The bottom milled for the key switch
Then I got it all chromed...
But man o man... that cost me some serious COIN. And its just ANOTHER reason why my tag says what it does above my avatar.
But damn it looks good when done RIGHT
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