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View Full Version : Ironhead hardtail off center by 1 inch-what to do?


fergerburger
28th October 2009, 07:02
so I'm getting to the bottom of the strip down of this 75 hardtail and I noticed that the rear rim is off center by about 1 inch. It sits 1 inch to the right of center. I measured out the hardtail and it is symmetric and not bent. The rim is aligned straight so the wheel is not cocked right or left. Can this be right on a hardtail add on???? Anybody got a weld on santee hardtail they can take a look at for me and advise?????

http://i700.photobucket.com/albums/ww7/0degreesf/75_hardtail/IMGA0715.jpg

78ironhead
28th October 2009, 07:17
You can shorten the left axle spacer and get a longer one for the right side. Then you may have to space the sprocket to line it up to the countershaft sprocket on the engine.

Hopper
28th October 2009, 07:17
Dont panic. The rear rim sits off centre in the stock frame too.
And the whole engine sits off to one side in the stock frame too.
Somehow it all seems to track straight going down the road.

Not sure exactly what your dimensions should be but I am sure one of the experienced custom builders will be along who can tell you more.

dr.feltersnatch
28th October 2009, 07:27
When you say you measured it how did you measure it? It looks to me that one leg is longer than the other. Is the wheel adjusters centered? If you have a work bench lay the frame on its side and clamp the back legs down flat and measure up to the neck then flip it over and do the same it should come out with the same number. Or find something straight and flat like a straight edge or maybe a 2x4 as long as you ist the same side and clamp it on there, but if you use a 2x4 make sure you out the crown in on both sides Measure from a fixed point like the end of the backbone to the tip of the tail on each side and it should be the same.

fergerburger
28th October 2009, 07:48
the guy ran the weld longer on that one side...I did square it off as best as I could with the front end on the bike and the hardtail seems relatively straight. At least the dimensions are close....I tried squaring the legs and measuring the axle plates distance from the backbone and these are within an 1/8 of an inch. The guy did not use a frame jig. He simply bolted the lower end to the stock frame and started welding and hacking. He claimed it ran straight but somehow the tranny blew the cases and after I took the tranny apart, I notices the mainshaft was shearing badly into the main thrust washer.

I'm a little worried. I can't believe I can run the bike with the rear tire an inch off center.

IronHead78
28th October 2009, 08:03
Dont panic. The rear rim sits off centre in the stock frame too.
And the whole engine sits off to one side in the stock frame too.
Somehow it all seems to track straight going down the road.

Not sure exactly what your dimensions should be but I am sure one of the experienced custom builders will be along who can tell you more.

Hopper is correct, one of the ways a hardtail is centered before welding is by running a string from the neck straight down the middle of the backbone down the middle of the hard tail. It's your wheel spacing

fergerburger
28th October 2009, 08:11
some more pics
http://i700.photobucket.com/albums/ww7/0degreesf/75_hardtail/IMGA0712.jpg
http://i700.photobucket.com/albums/ww7/0degreesf/75_hardtail/IMGA0713.jpg

dr.feltersnatch
28th October 2009, 08:20
It looks to me like the right side is longer than the left side. Wheel spacing will center your wheel but it looks cocked to the right not off center to the right. I could be wrong the screen on my blackberry is only an inch and a half so its kind of hard to see.

fergerburger
28th October 2009, 08:45
I think the right side is longer. The problem now is what to do. I need a frame jig to get this fixed and I do not have one. I know that the weld on hardtails do not line up very square when you bolt them on from the bottom. If you think it's square and start welding, you end up with what I got from the PO.

I'll make some calls tomorrow and see if anybody in Minneapolis has a frame jig

Hopper
28th October 2009, 10:38
Hard to tell just what is going on by the pics, kind of dark in there. But the one with the straight edge laid on top of the frame backbone, is that sitting over top of the top frame backbone or off ot one side? If sitting right on top, your wheel is offset by about 3/8" which is about right, sort of.

But then the wheel looks definitely crooked in there. Might just be a matter of kicking the wheel around??

misterT
28th October 2009, 10:42
If you can't find a frame jig you could bolt a long straight bar through the wheel adjusters with an equal distance on each side. Then measure from the ends to the front of your frame it should form a symetrical triangle.

Ferrous Head
28th October 2009, 11:41
Not trying to be funny here but has anyone checked what happens in a stock frame ? If you have the cases there bolt them in and check to see where the sprockets are. The sprockets need to be in a straight line. Centering the wheel is not quite as important as some would believe. If you look at how "centered" the Sportster engine is in a stock Sportster frame you'll see that it just plain isn't. It's offset. ie centerline of the frame and centreline of the engine don't match.
Go and check a stock frame wheel combo before you do anything else. I have a suspicion you'll find the wheel isn't centered along the frames backbone.

fergerburger
28th October 2009, 17:10
If Hopper is right, and I bet he is, the stock offset is 3/8th to the right. I think I am 1/2 off to the right not 3/8th which is not too bad. However, the wheel is not crooked as Hopper suggested. It looks crooked because the guy that welded the hardtail has the triangle cockeyed...yeah..."cockeyed"? Like a chicken lookin' sideways at somethin'

He welded the right leg a little farther up the backbone. Probably because the cheapo hardtail piece was crooked and he did not have a frame jig. I need to decide if I should cut the rear legs from the down tube and re-weld....This may ruin the damn thing.

Maybe I'll call Kansas Kustom and see what they have to say. They have a unique hardtail for the ironhead.

snowman
28th October 2009, 17:17
You can shorten the left axle spacer and get a longer one for the right side. Then you may have to space the sprocket to line it up to the countershaft sprocket on the engine.

This will solve the problem if you measure from a front point on the frame
to the rear axle openings and they measure the same on both sides...:geek:geek:geek

fergerburger
28th October 2009, 18:26
It's gonna be off. I checked the triangulation of the hardtail to the downtubes and it was not equal lengths to the axle boxes

ryder rick
28th October 2009, 19:01
You cannot move the wheel sideways in the frame to center the wheel.
Your first concern is chain alignment.
Place a straight edge on both sprockets and they MUST point at each other and be parallel for the chain to run straight.
Then you can move the tire into the center of the steering axis, with the sprocket aligned the rear tire must be centered on the steering axis or the bike will not track correctly.
Both the steering axis and the vertical centerline of the rear tire must also be on the same plane for proper tracking.
Centering the wheel on a drum brake hub can be done by offsetting the rim on the hub, as long as you don't get the tire into the chain.

There are more options on a disc brake wheel as you can space the sprocket, use a dished sprocket, etc.

fergerburger
28th October 2009, 20:07
why can't I space out the drum and drum cover with a spacer? cut 1/2 off the left axle spacer and space out the drum and the cover 1/2 inch.

ratbit
28th October 2009, 20:25
Take a look at your first photo. The right side is definitely longer than the left. It is not an optical illusion. You can put a straight edge accross the back of the frame and measure to the front at a good reference point. It ios longer on the right side.

snowman
28th October 2009, 20:33
It's gonna be off. I checked the triangulation of the hardtail to the downtubes and it was not equal lengths to the axle boxes

This is the critical measurement.

How far off was it? +- .125" is not a problem...:geek:geek:geek

fergerburger
28th October 2009, 21:38
it was more than 0.125. I'll pull it apart tonight and get exact measurements.

I called Bill at Kansas Kustom and I may use there hardtail option. It eliminates the double downtubes and would fix all this mess....it will set me back 600 bucks though

sddowdy
28th October 2009, 22:34
For less than $700 you can get a new hardtail frame from Jireh Cycle, and sell the frame you have. Just a thought.

ryder rick
29th October 2009, 00:18
why can't I space out the drum and drum cover with a spacer? cut 1/2 off the left axle spacer and space out the drum and the cover 1/2 inch.

You could, but what is that going to do to chain alignment?

fergerburger
29th October 2009, 01:02
chain should be fine...right? I'm spacing out the sprocket to line up with the drive sprocket. It takes 2 spacers. One for the drum to hub clearance, and one for the brake cover to hub spacing. If I move the drum and sprocket out 1/4 inch, I should be able to center off the rear wheel.....

Anyway, the right leg is longer by about 1/4 inch which means you have to tilt the axle in the mounts. It's was off and will have to be removed and rewelded with the use of a jig. What a pain in the ass.

As far as buying a new frame, maybe that's the way to go...but I got this thing with the intention of "saving" it.......

dr.feltersnatch
29th October 2009, 01:23
I agree save it, it just needs some love. I would think any decent fab shop could get ya going for not too much. A frame jig would be nice but not a deal breaker for a decent fabricator. Check around there has got to be someone close

fergerburger
29th October 2009, 03:46
check out the backbone to down-tube. he welded nubs on the top of the down tubes and seems to have mis-aligned the backbone to down-tubes as well. on my other bikes, the backbone seems to split the down-tubes symmetrically but I could be wrong.
http://i700.photobucket.com/albums/ww7/0degreesf/75_hardtail/IMGA0719.jpg