Magna Owners Of Texas

Public Forums => The Garage => Topic started by: Lurkin on January 06, 2009, 03:23:59 PM

Title: Drilling Backrest
Post by: Lurkin on January 06, 2009, 03:23:59 PM
I need some advice from you DIY types.  I recently acquired a Corbin Gunfighter seat.  Since my boys (10 & 13) still ride with me, my Hondaline backrest must stay, but it looks quite tall with the Gunfighter.  I test fitted moving the backrest down by unbolting the backrest "hoop" from the mounting tabs, lowering the hoop's top mount hole to the tabs's (sp?) bottom mount holes.  This would lower the hoop by almost 2 inches, but it would require two new holes to be drilled into the hoop.

What I am looking for is experiences/advice on how (or if...) I should drill new mount holes into the hoop.  Since the hoop is chrome plated solid aluminum (I think it's aluminum anyway due to the weight), I am worried about drilling through the chrome and what affect (cracking, flaking, etc.) the drilling may have long-term.

What do y'awl think?

Rod..
Title: Re: Drilling Backrest
Post by: hootmon on January 06, 2009, 03:34:32 PM
I don't think it is Aluminum..
I don't think you will have any issues with drilling it with a HSS drill bit. You will of course leave a place for Rust to start since the new hole will not be chromed.. I say - Go for it..
Before and after pictures please.. With the required SeaFoam can in the background..
Title: Re: Drilling Backrest
Post by: TLRam1 on January 06, 2009, 04:08:47 PM
Rod, I think it's hollow chrome plated steel. Should not be difficult to drill new holes, use a nail set or center punch to make a small impression to keep your drill bit from walking. A little silver paint to protect the bare metal around the holes. You can use nylon or rubber plugs to fill the empty holes if you move the hoop back up.

Photos are a must.
Title: Re: Drilling Backrest
Post by: Lurkin on January 07, 2009, 08:06:05 AM
Hoot, Terry, thanks for the input.  It isn't solid, as you've stated, and I knew that since the bottom of the hoop is hollow.  That's what happens when you don't think things through :-)  But the existing holes must be sleeved as they are not hollow at that point.

But I still a bit concerned with the chrome flaking or cracking when drilled.  Has anyone drilled into a chromed item, and what were the results?

I did pick up a new (openbox) backrest on eBay last night for $60, so if I do screw it up I can get back to where I was.

Rod...
Title: Re: Drilling Backrest
Post by: hootmon on January 07, 2009, 08:10:23 AM
Quote from: Lurkin on January 07, 2009, 08:06:05 AM
But I still a bit concerned with the chrome flaking or cracking when drilled.  Has anyone drilled into a chromed item, and what were the results?
I've never had a problem with drilling chrome, other than rust later due to the removal of the protection by the chrome...
Title: Re: Drilling Backrest
Post by: Cannon on January 07, 2009, 12:31:19 PM
I've done this with my stock Hondaline backrest. I choose to cut the lower ends, and did this just above the original lower holes. The old upper holes became the new lower holes. The new holes and cut surfaces was sealed with silver paint.

I also cut the top off the backrest pillion, so that it only sticks 1 cm over the chrome sissybar frame. This forced some sewing. I could bring pictures, but I cant get hold of any seafoam cans here in Norway :sad: :D

This mod added quite good to the appearance. The backrest pillion is now nearly touching the rear stock seat. The added support of the lower back also feels better for the passanger.
Title: Re: Drilling Backrest
Post by: TLRam1 on January 07, 2009, 12:45:50 PM
Steal Hoots seafoam and run! Throw up some photos, I'd like to see.

No problems drilling chrome here either. If you could drill a large enough hole to fit a spacer in might be something to think about. 
Title: Re: Drilling Backrest
Post by: rjb/AKA Bob Barram on January 07, 2009, 02:36:27 PM
I may be doing this also to the Rocket luggage rack. The R3 forum suggests it as an alternative mount for the license plate. To attach the bracket the drill holes for mounting the bracket.
Title: Re: Drilling Backrest
Post by: Lurkin on January 07, 2009, 02:55:05 PM
Again, thanks for all the input.  I figured someone(s) had done it before, and wanted to set my mind at ease.

We'll see about any pictures when the time comes.  I usually don't want too much proof lying around :-)

Rod...
Title: Re: Drilling Backrest
Post by: Cannon on January 07, 2009, 04:17:46 PM
Quote from: TLRam1 on January 07, 2009, 12:45:50 PM
Steal Hoots seafoam and run! Throw up some photos, I'd like to see.

No problems drilling chrome here either. If you could drill a large enough hole to fit a spacer in might be something to think about. 

I think maybe larger holes for spacers would weaken the backrest too much? The upper boltholes are the most stressed points of the construction. 

And for the seafoam; will a norwegian beercan do the trick, or....... :?
Title: Re: Drilling Backrest
Post by: TLRam1 on January 07, 2009, 04:54:06 PM
Yes, I was wondering about weakening the area but didn't look at mine to see. Throwing ideas out for someone to come up with a better one.

Let's see the beer can!
Title: Re: Drilling Backrest
Post by: Lurkin on January 08, 2009, 09:21:10 AM
Terry, I was actually thinking the spacer thing yesterday after the reminder that the hoop was hollow, but I came to the conclusion that it would weaken it too much unless I tied it into the hoop, i.e., welding.  But welding on it goes further then I wanted to go, as it would need significant cleanup after welding to adhere to my aesthetic requirements.  BTW, keep throwing out the ideas and thoughts, it's all good.

Cannon, why did you cut the bottom of the hoop off, since it just needs to be moved down?  I assume it was for the aesthetic reasons I mentioned above for myself, since you also trimmed the pad down.

Also, don't pay too much attention to the "can" fetish boys, or is it "Foam" fetish.  Next they will ask you to post picks of a can with the top popped....  I think Terry spends too much time on those two strokes and explosion-mouting car tires on MC rims, and Hoot,,, I think it's just a Florida thing.   :grin:

...all in jest !!

Rod...
Title: Re: Drilling Backrest
Post by: Cannon on January 08, 2009, 02:41:37 PM
Hi again
I cut the hoop ends because they would conflict with the chrome "liners" of the back fender.
The hoop is solid steel, at least mine is. For the drilling; Sharp drillbit, medium/low drilling speed and keep the drillbit point oiled. Awoid heat building up.

When trying to add pictures I get message; "Error. Upload folder is full" :sad:
Title: Re: Drilling Backrest
Post by: TLRam1 on January 08, 2009, 03:07:18 PM
Quote from: Cannon on January 08, 2009, 02:41:37 PM


When trying to add pictures I get message; "Error. Upload folder is full" :sad:

Go into the MOOT Business area and there is a photo hosting site you can use, with a How Too explanation.
Title: Re: Drilling Backrest
Post by: Cannon on January 08, 2009, 03:31:36 PM


Go into the MOOT Business area and there is a photo hosting site you can use, with a How Too explanation.
[/quote]

I can't find the Business area. Maybe because I'm a guest member?
Title: Re: Drilling Backrest
Post by: TLRam1 on January 08, 2009, 03:44:34 PM
Quote from: Cannon on January 08, 2009, 03:31:36 PM


Go into the MOOT Business area and there is a photo hosting site you can use, with a How Too explanation.

Quote

I can't find the Business area. Maybe because I'm a guest member?

Could be, I didn't know we had Guest Members. I thought once you are able to Post you could go anywhere on the forum.
Title: Re: Drilling Backrest
Post by: Lurkin on January 12, 2009, 08:40:13 AM
Well, I wasn't actually intending too, but I did the drill out thing on Sunday.  I was in the garage, trying not to shiver too much (Texas Gulf Coast cold anyway...), doing some odd jobs and clean up and decided to take the backrest hoop off to look it over and do some measurement.  Next thing I know, it's drilled out and done...

No pics though since I did it as a spur of the moment thing.  It does look much better.  Just for info, as Cannon said, it is solid metal, not aluminum, but not exceptionally hard metal.  I drilled each side through in 3-4 steps to help control the heat generated.  The chrome held, as you all expected, and the holes drilled through clean.

If you want pictures, visualize your backrest 1 5/8" lower :-)  Like I said, looks much better with the Gunfighter seat, and I can still raise it up for my Mustang seat (or the stocker if _absolutely_ necessary).

Rod...
Title: Re: Drilling Backrest
Post by: Magniac on January 16, 2009, 06:28:46 PM
If it's the stock Hondaline backrest, it is hollow and I would be very leery of weakening it. It's the same material as the luggage rack. See my post about the heavy duty luggage rack several weeks ago :?.
Title: Re: Drilling Backrest
Post by: Magniac on January 16, 2009, 06:32:54 PM
P.S. The post about the luggage rack is on p. 6 of "garage"
Title: Re: Drilling Backrest
Post by: Magniac on January 16, 2009, 06:35:13 PM
Oops, I missed the part where you said it's solid metal. Sorry
Title: Re: Drilling Backrest
Post by: Lurkin on January 19, 2009, 03:43:10 PM
Yup, I've drilled into two of 'em now, and they were both solid.

Rod...