SuperMoto Junkie banner

1 - 13 of 13 Posts

·
Registered
Joined
·
448 Posts
Discussion Starter #1
got a little ding on my headpipe a few weeks back at a stunt show. Its a long story, but my header ended up ganging into an akrapovic header on my buddies R1 - which happens to be a bit thicker - and dented it pretty good. Like i said - long story, but his R1 was up in a full-on stoppie which brought his header up to the right height. The lighter color is the ceramic heat coating that rubbed off of his header onto mine.

Onequickpuck is a master metal worker here locally and helped me rebuild my head pipe. We removed the section of pipe with the dent and replaced it with a piece of same-sizes, slightly thicker GSXR pipe. (it wont dent as easily now!)

Then i wanted to make my own power bomb, so I turned down some stainless barstock on his lathe to make a mandrel with an angled end, slipped some 2" SS exhaust tubing over the mandrel and while he heated it up with a torch, i used the lathe to roll the 2" stock down to meed the angle on the mandrel. The tool i used was actually a transmission bearing i removed from my 426 during rebuild, welded to a tool bar so that it would roll against the tubing.

I turned the two halves down to fit together like an easter egg before he welded them. No welding lips on the inside - all smooth. We were in a hurry so he tigged them up as fast as he could. The insides are perfect, even though the outsides are a little rough looking. The inside is what counts.

My bike is probably no faster, but it was fun making it, and it looks neat. lol.

Two yamahas cannot occupy the same space at the same time, no matter how hard you try.


Mandrel out of SS barstock.


SS tubing tacked to mandrel and rolled to follow the radius on the end.


Both halves before cutting down to size.


Machined to fit together like an easter egg.


Before welding.


Tacked the original pipe to a jig to hold everything in place. cut, and re-welded.
back-purged the entire pipe with C02/argon mix to keep the welds on the inside from building up slag.


On the bike...
 

·
Registered
Joined
·
3,999 Posts
Nice work fellas!!! Great show of team work and how ingenuity over comes a issue to find a solution, that looks good.
 

·
Registered
Joined
·
448 Posts
Discussion Starter #6
orginal power bomb is not that simple..
explain?

we took some rough measurements off a header pipe that had a powerbomb on it for another 426 that my friend had at his shop. By rough, i mean, rough.

the powerbomb we looked at was hollow, and the slip fittings they did before welding left lips on the inside against the flow of exhaust. All our inside lips are smooth and go with the flow. (i.e. theres no lips for the exhaust to hit - its all smooth).

Thats about as techincal as we got.

The bike already runs strong so its hard to tell any difference. It'll outrun a KTM 525 on the highway as well as a Suzuki650 dualsport with a pipe, and it'll hold a max speed of 106 on gps. nothing astounding, but for an 8 yr old bike she does OK.

ALMOST hangs with a KTM 560 on the front straight at Hallett, but NOT QUITE. maybe with different gearing more closely matched to the 560's.


The original project was entirely done to fix the dent in the pipe... it turned into one of those... "while we're in here... lets do...."
 

·
Registered
Joined
·
37 Posts
Show off! Haha just kidding! I think the main upgrade is now the 426 makes 308 decibles instead of the stock 305. It turned out looking awesome too.

Apa, as for the perforated tube inside the FMF power bomb. I brought this up to the guys when they were building it, so we looked at the FMF we had there and to my suprise there was no tube inside of it. I've see the pictures of it in catalogues but there wasn't one in the FMF we had on hand.
 

·
Registered
Joined
·
954 Posts
Dude, that was some sweet fab work!! Actually, that was a pretty sweet idea turning down the pipe with the bearing. Hmmmm I'm gonna have to file that little nugget away for safe keeping!

Looks great, good work!
 

·
Registered
Joined
·
448 Posts
Discussion Starter #10
i see what you guys are talking about, but the one we looked at had NOTHING inside and was completely hollow.

weird.

I guess i'll throw the GPS back on and see how it affected my top speed.

I really need to re-jet this bike too (have need it for a while) but with my '07 KTM SMR 450 purchase, the 426 may get less attention now...
 

·
Registered
Joined
·
1,524 Posts
:thumbup::thumbup::thumbup::thumbup:

Good job.
 
1 - 13 of 13 Posts
Top