Header modification

[reddirtrider]

I've recently picked up a Yoshi header that I want to use on the '83 GS750ES. The problem is that the flanges were the wrong ones for this bike. I have a set of flanges left over from another project that will work, so I cut off the pipe section that overlays the header and can now put the new flanges on.

The question I have is what to use now for the overlay. I was thinking of getting some 1/16th sheet and cutting it to the width I want, then heating and bending it around the pipe and tack welding it in place. I'm not so sure this is the easies method out there.

Any ideas? I know someone has something better.

Below is a pic of the header with the new flange on the right. The color differential is due to the fact that I've sand blasted part of the header.

Damn, thought I had this img thing figured out. Guess not.

 

[reddirtrider]

Someone referenced exhaust tubing from Summit in another post so I went there to check around. I'll order a piece of 1.75" 16 guage stuff and cut a slice in it so that it can be shrunk. That's probably the easiest solution I've found.

Thanks for the tip.

 

[posplayr]

Red,
Ray suggested taking an die grinder and elongating the flanges. The SS flanges are expensive, but on my Yoshi, the collars will come off fairly easily so I might just swap the flanges but avoid cutting the actual tube.

related thread.

http://www.thegsresources.com/_forum/showthread.php?t=143149

Pos

 

[reddirtrider]

Red,
Ray suggested taking an die grinder and elongating the flanges. The SS flanges are expensive, but on my Yoshi, the collars will come off fairly easily so I might just swap the flanges but avoid cutting the actual tube.

related thread.

http://www.thegsresources.com/_forum/showthread.php?t=143149

Pos

I already thought of that and rejected it. It's probably a bit easier, but I already have the correct flanges and I'm anal.

 

[reddirtrider]

I figured out how to create the new sleeve.

I purchased the tubing in an earlier post from Summit, cut it to 3/4" lenghts and cut a slice out of it so that I could reduce the diameter. I then drilled some holes so that I could weld it on the header (I don't have a spot welder). I'll try to include a pic, but I'm failing miserably and I don't have much patience with software that doesn't work properly (The icon to insert image doesn't work for me).

Now all I have to do is finish the other 3 tubes and paint it. The Tech Line stuff from Caswell looks good since it air dires.

 

[posplayr]

Red,
You did such a good job welding it is hard to tell what you did. Can you do a pic of the parts (after modification but) before welding. It looks like the distance from the end of the pipe to the flange is way too long on the original pipe. What pipe are you using?
Pos

 

[reddirtrider]

Red,
You did such a good job welding it is hard to tell what you did. Can you do a pic of the parts (after modification but) before welding. It looks like the distance from the end of the pipe to the flange is way too long on the original pipe. What pipe are you using?
Pos

I'm not really that good of a welder, but thanks.

I'll take more pics now that I know it works. It's a Yoshi I bought off Ebay. The seller said it was for a GS750, not sure of the year but earlier than an '83 for sure. It's a meg and I happen to have a thing for them.

I knew I might have to do some mods to make it work right. The bike it's going on is an '83 GS750ES.

 

[reddirtrider]

Ok, more pics ont he process as I promised. The first shows the three stages of the sleeeve prior to installation.

On the left it's just been cut from the 1 3/4" 16 gauge header tubing to a length of 3/4". I used a hack saw, but if I was going to do this for a living a portaband sure would be nice. You can get a fairly straight cut by wrapping tape around the pipe as a marker, then rotating the pipe as needed to stay on the tape line. I used a file to clean up the edges.

The middle has a notch cut out so that the flange can be pulled in to the Yoshi pipe and the right has holes drilled so that I can weld it as I do not have a spot welder.

 

[reddirtrider]

The next pic shows the welding process. I held the flange on either side of the hole tight to the pipe, then put down a bead and moved to the next. The finishing weld was done to join the notch cut.

 

[reddirtrider]

This is the pipe after welding and a bit of cleaning up. The fit to the '83 GS750es is very nice from the down tubes to the collector. The meg portion will need a bracket fabbed to fit to the mounting area on the rear peg bracket, but it looks pretty good aesthetically. I'll post more pics as I progress.

 

[posplayr]

Mystery Solved

Mystery Solved

Red,

So thats how they do that .
Thanks that shows what you are doing nicely. I have a cheap HF wire feed that I dare not use on my header as it splatters too much but this is motivating me to buy a better one.

Jim

 

[reddirtrider]

Red,

So thats how they do that .
Thanks that shows what you are doing nicely. I have a cheap HF wire feed that I dare not use on my header as it splatters too much but this is motivating me to buy a better one.

Jim

I have a pretty nice wf (Miller), but you are probably using flux core if you're splattering. Do you have a provision for gas shielding, if so I highly recommend it - then you can use solid core and there's no splattering. Also, get a self darkening helmet as it really does make it a lot easier to start and stop on small welds.

 

[reddirtrider]

One more thing. Welding is most forgiving. If you make a mistake, grind it out and start again, or fill it and grind. This isn't structural welding, which is another story. This is pretty easy stuff and the only thing you need to make sure of is that you're not too hot and burn holes through the material. I'm sure any one of us in here can do it if I can.

 

[reddirtrider]

I thought I had some pics of removing the old flange, but can't find them.

The way I did it was use a cut off wheel on a grinder and cut a notch through the old flange just to the point where it ends - without cutting through the header pipe. I then pried it up a bit and used a pair of vice grips to peel it away. When you come to a spot weld, get the grinder and cut through it, then move on. You can use brute force to peel through the spot weld, but it distorts the pipe a little and you have to deal with that later.

Grind the spot welds down and you're ready to mount the new flanges.

 

[reddirtrider]

Ok, her's a pic of the unpainted header on the bike after the modifications. I had to fab a bracket for the meg and dent the #1 tube for clearance on the oil cooler fitting, of course the mods that started this thread, but all in all it looks pretty good - to me anyway.

 

[reddirtrider]

Here's a pic of the bracket. It needs a lot more work, but I wanted to get a pic of it to send. I'll clean it up, cut it back a bit so it doesn't show so much, and then paint it. Notice that I left the Yoshi tag on the meg chrome. I'm going to use satin black ceramic paint on the header and hopefully that chrome tage will set it off nice.

 

[reddirtrider]

Here's one of the dent I had to put in the #1 tube for clearance on the oil cooler bolt.

 

[reddirtrider]

One last shot of the clearance on the lower shock mount. I'm still waiting on the shock bushing for the Ducati shock so hence ut's not bolted up properly in case you noticed.

BTW, I believe this was a pre-'83 GS750 header, so it will fit an '83 it jsut need some mods. Next up is ceramic coating and I'll post some pics then.

I love Yoshi megs - they are so clean and it sounds great too.

 

[reddirtrider]

Here's a pic of the meg end after laying on the ceramic coating. This is before any baking. The instructions say 750 for 1 hour, but I don't have an oven that will do that, so I'll try 500. The head pipe portion will be baked on with the exhaust heat, which the instructions say is ok.

The instructions also say to use a touch-up gun or airbrush, but it was a disaster when I tried to use the airbrush. So, I stipped it off using acetone and got out the hvlp gun and shot it. I'm happy with the results. I'm sure a professional shop would do better, but Hot Jet quoted me $250 and the ceramic coating was only $50 for this job.

The wife even let me put it on the bed - now that's a clean motorcycle part! I left the badge chrome. The contrast looks good.

 

[reddirtrider]

Here's a shot of the entire meg section.

I'll post more pics later once it's baked, then a final one on the bike.