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R1150RT Exhaust Welding

roger 04 rt

New member
There was a lot of good discussion of welding techniques in the "Bolts" thread.

I'm probably going to add a second bung to my exhaust system (R1150RT) so that I can run both a stock O2 sensor and my wideband O2 sensor side-by-side. I don't know any welders in the Metrowest Boston area nor do I know what I'm looking for--skills, equipment, etc.

Does anyone have a recommendation of a welder in my area who does neat work or could you point out what I would need to ask? Also, does anyone have any thought on where I should locate a second sensor (I would only use the mount temporarily?

RB
 
Find your nearest welding supply store and ask the guy behind the counter. He'll know which of his customers to send you to for any type of work. I did this when I needed an aluminum plate welded to the intake of my race car.
 
There was a lot of good discussion of welding techniques in the "Bolts" thread.

I'm probably going to add a second bung to my exhaust system (R1150RT) so that I can run both a stock O2 sensor and my wideband O2 sensor side-by-side. I don't know any welders in the Metrowest Boston area nor do I know what I'm looking for--skills, equipment, etc.

Does anyone have a recommendation of a welder in my area who does neat work or could you point out what I would need to ask? Also, does anyone have any thought on where I should locate a second sensor (I would only use the mount temporarily?

RB
Ideally you would want to have that TIG welded Roger, TIG will give you the neatest appearance on thin metal. If you were stuck and I thought MIG welding would give you the best results, I'd have you stop by. I don't know any of the welders in MetroWest but the poster that mentioned checking with a welding supply has a good idea. Chances are that there is an AirGas in your area. Good luck. Gary
 
Buy a bung and plug at an auto parts store. Advance has them.

If you can't find a welder, send it to me. I'll tig it in. If you want to run with the o2 sensor out, then you can just install the plug.

110 volt Mig with .023 wire should weld it in fine.

I don't know if you could find a stainless steel one.

David
 
Find your nearest welding supply store and ask the guy behind the counter. He'll know which of his customers to send you to for any type of work. I did this when I needed an aluminum plate welded to the intake of my race car.

Ideally you would want to have that TIG welded Roger, TIG will give you the neatest appearance on thin metal. If you were stuck and I thought MIG welding would give you the best results, I'd have you stop by. I don't know any of the welders in MetroWest but the poster that mentioned checking with a welding supply has a good idea. Chances are that there is an AirGas in your area. Good luck. Gary

Buy a bung and plug at an auto parts store. Advance has them.

If you can't find a welder, send it to me. I'll tig it in. If you want to run with the o2 sensor out, then you can just install the plug.

110 volt Mig with .023 wire should weld it in fine.

I don't know if you could find a stainless steel one.

David

Many thanks for the replies. I'll start to look and ask around for someone with a TIG welding capability. I've got a bung that came with the O2 sensor but its a deep bung so I will go the the parts store and get a bung plug combo.

I'm not sure about the exhaust or bung materials. Will there be any welding compatibility issues?
 
Many thanks for the replies. I'll start to look and ask around for someone with a TIG welding capability. I've got a bung that came with the O2 sensor but its a deep bung so I will go the the parts store and get a bung plug combo.

I'm not sure about the exhaust or bung materials. Will there be any welding compatibility issues?

A steel bung can be welded to a chrome exhaust. A steel bung can be welded to Stainless exhaust, but the
bung will rust and so will the weld. Stainless bung and stainless exhaust need to be welded with pure argon
shielding gas (tig) and stainless filler. They will not rust.

So yes any bung can be welded to any exhaust. Some will be prettier than others.

David
 
Thanks so much David. I wouldn't have thought about the rusting. Could those parts be effectively painted if not SS? There isn't any rusting of my existing bung that I'm aware of so I guess it's SS?

Innovate, the makers of the Wideband kit make a SS combo that Amazon sells for under $10. Thanks for the tip.
 
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Cut a bung out of a retired cat and TIG weld with SS filler rod. No rust issues.
Any good welding ship can do this for you.
 
AEM makes a No-Weld O2 Sensor bung that is a clamp with bung and strip of adhesive. I thought about it for a while and decided against it.

There are surprisingly few good spots on the R1150RT to mount a second bung but It looks like the weld-in bung will fit on top of the cat/muffler about a half inch back from the attachment clamp. I found a photo (below) that shows the stock O2 sensor mounted on the inner side of the feed tube to the cat. It appears that there's clearance if I mount the bung on top and near the front.

An advantage of that spot is that it will free-up about a foot of the wideband sensor's cable that is used now to reverse course and clear the transmission. A downside is that I think the sensor would need to be removed before removing the exhaust.

a20791812f79baa07da800_m.JPG
 
I have cut apart the muffler you are looking at. (one just like it) Its stainless for sure. The cat is just around the corner from where the pipe goes into the muffler. If possible I would keep your new o2 sensor close to the original one.

The cat is on the same tube as goes into the muffler, so its a double wall thing. If you put the sensor in the muffler part, it may not work. The cat is only in the first third part of the muffler looking section. Its walled off from the rest.

The exhaust leaves the cat, goes up a tube that goes to the end of the entire muffler, then back into the squareish part, then back out the middle, so the exhaust travels 3x the length of the round muffler part of the exhaust.

Hope this helps.

I screwed with the fuel in my oilhead quite a bit, in the end I used a techlusion and rode the bike till it wore out. A little more fuel really brings it to life.

Watching for your results. My offer still stands. Send me the muffler, I will weld in the bung. No charge.

David
 
Thanks for all the detail and offer to do the welding, I know it's sincere. Now that I know where to put the sensor and what kind of welder I'm looking for, I'll see if there's someone within a few miles of where I live.

Here's a spot where I can get a wrench on the sensor and it's only about an inch from where the stock sensor is mounted. It will at least do as a spot for an O2 sensor to be tested and may even be better for the LSU 4.2 Wideband eventually.

My understanding is that I drill a hole in the exhaust the diameter of the bung and then the welder sets it up and welds it in. In the photo below I'm showing it with the long mild-steel bung that came with the unit for mounting in high temperature locations but I will go with a usual height bung when I get it installed.
 

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Thank you all for all the help. I found a good guy locally with TIG capability. He mentioned to me that he got a good enough fit and didn't even need filler rod.
RB
 

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You found your self a good stainless welder. :clap

Looking for results now.

David

The exhaust is back on with two sensors and I've begun taking data on the stock O2 sensor. For the first time we'll have some good plots of what is actually happening to the mixture using the stock sensor.
 
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