Frame repair

[CMcQuay]

I went and dug my old bike out of the barn to fix for my son. I don't remember cuting the frame on this one but some one did. I have another frame with a section cut out that still has the down pipe that was cut, it is safe to cut the whole bar out and replace it? Any ideas welcome and thanks in advance.

 

[Longview]

Well i learning in a Pre-Welding class at my school, that the spot you weld is actually stronger than the material your welding with. So I'd think it would be alright.

But don't take my word for it, I'm no expert.

 

[Blaaster]

Well i learning in a Pre-Welding class at my school, that the spot you weld is actually stronger than the material your welding with. So I'd think it would be alright.

But don't take my word for it, I'm no expert.

In some way you are correct, the welded area can be stronger than the parent metal, but there is a downside.

The areas close to the weld can suffer crystalisation because of thermal disturbance.

Butt weld the ends, and if it were me I would be putting a brace on the innerside where it may not be noticed.

 

[Longview]

In some way you are correct, the welded area can be stronger than the parent metal, but there is a downside.

The areas close to the weld can suffer crystalisation because of thermal disturbance.

Butt weld the ends, and if it were me I would be putting a brace on the innerside where it may not be noticed.

Not to hijack, but Crystallization is what causes the metal to become weaker?

 

[CMcQuay]

I was thinking replacing this bar and adding the gussets(sp), a machine shop would be doing the work

 

[CMcQuay]

BTW the black framed bike is the one I am wanting to fix.

 

[dksix]

Not to hijack, but Crystallization is what causes the metal to become weaker?

It becomes more brittle and prone to cracking.

I would be more inclined to fix the frame missing the top tube if that's all that's wrong with it. Butt weld a new section into it with a inside splice about 2 inches long (1" on each side of the weld). Put a chamfer on the outside tubes, try to get them a square to each other as possible and weld all 3 pieces together. If you get good penitration into the splice piece you'll have a weld you won't have to worry about.

 

[CMcQuay]

Back end of the silver frame is jacked up bad. Would I be better off looking for another frame with no damage?

 

[Larry's Shee]

Different frame would be easiest and probably cheaper if you were going have someone else do the work

 

[Blaaster]

If you are going to give the frame any type of punishment, rough terrain or jumps, then I feel that another frame would be the best bet!

 

[CMcQuay]

I looked on eBay and looks Like a frame shipped is only a couple hundred, but what is the difference between the 88-02 and 03-06 frame?

 

[dksix]

There is a bracket for lugs on the back of an 03+ head light and another for the bolt that holds in on the front. The 03+ has the mount for the rear brake master cylinder and 1 for the reservoir. The 03+ had places to bolt brake line brackets on the upper A arms, that's all I know but there may be more.

 

[Larry's Shee]

03+ won't have bracket for rear cable. I would look on CL and pick up aframe local and save shipping. I wouldn't pay much more than 100 for a frame local

 

[mud runner]

ya we paied 150 for our other frame and got it delivered to our house for free and all that was missing was the carb motor and plastic