my mid pipe frame tab cracked off I need it welded back on. my question is what electronic components should I disconnect if any at all and what is necessary to prevent any electrical issues in the system. I assume unplug ecu and unplug the stator, yes?
truth is I swear there is less vibe in the chassis without that tab connected- 2 muffler mounts onto the plastic subframe and the forward iso mount along with the dual springs for the cylinder attach point.
I've rewelded pipe brackets on several bikes. sometimes forgot to remove the battery. Still no problems. never unplugged the ecu. but hey, couldn't hurt.
No everytime ive welded cars vans or my bike it only suggests battery, my theory being if theirs no circuit then the discharge will be through the welder only, also try to get as close to the weld with the earth clamp, voltage drop will be minimal.
it's a fast removal right? I'd take it completely off... maybe the regulator too. The current on a MIG or TIG is usually way less than the big ol Lincoln arc welder- but induced currents don't always need a complete circuit to generate damaging voltages (think of antennas) . Cheap/easy insurance. [cracks me up: whenever you're quoted robert- you can see your member number(=10! Coffee is 2- I would've assumed 0 or 1); you're the longest active member by a long shot. BTW, i'm like #60,000 or something with the new account after the spam attack last year. anyhooo- thanks for your posts here and TT- always entertaining and/or informative and a good read] I gotta image the AR-types over at KTM talk would say strip the frame bare and put it in a Faraday Cage before welding, but.... you know.
As an electrician I would suggest,besides disconnecting the battery, to pull the plug on the ECU. Only takes a minute and cheap insurance. A lot of welders use high frequency start, not gentle on electronics, it's recommended to turn it off in hospitals and the like. Also as suggested by juicypips, get the earth clamp as close to the welding as possible.
I had lower pipe mount welded n didn't disconnect anything(no battery though). As juicy said earth as close to weld as possible. Did hold my breath wen starting afterwards though haha. If it's easy to do then yeah cheap insurance to disconnect ecu etc
A friend of my brother inlaw welded a implement hooked to his new john Deere tractor fried the computer brain on the tractor... $3,000 fix !
Yeah but its a crappy john deere what do you expect? Opening a can near one of those would probably break the window.. (Watch the shit storm boys) Yeah im out voted looks like you disconnect ecu.
As usual ideas are here are great thanks all. Yes I will better safe than sorry disconnect the stator and ecu.....but I decided because of time to prep I will ride the bike as is for this weekends "extreme enduro" trail ride. I will target next week to make the permanent repair. I think however I will reattach the iso mount to the pipe and lay the mount bracket as close to in place as I can and put a big old chunk of hand mold epoxy over the thing and around the frame attach point to add some support. If it falls off no worries. Just a temp fix for the weekend.
I would do just the opposite. I would remove the remaining bolt on brackets. By leaving it bolted in place the edges will vibrate against each other and wear, opening the gap. making it harder to reweld later. if you glop on a bunch of epoxy, you'll have to chip it off and clean up the area before welding. I've ridden whole seasons with missing pipe brackets. I don't think 1 race will hurt it.
thanks Darkside very good points. and like I said above I rode the crap out of the thing last Saturday and I swear it actually felt smoother without the mid pipe mount . plus this am I actually kicked the chamber a couple of time just to see what impacts would do and where the pipe would move, it gets a little close to the lower corner of the radiator, but it could do that probably with the mid pipe mount on anyway. For now with all of y'alls suggestion I will stop thinking about it and just ride it as is, next week we can get that thing welded. Oh side note the crack was about 80-85% corroded/oxidized, so the thing had been cracked for quite some time, there was only a small section of clean metal along the broken off piece edge, where it finally seperated.
if you don't wire it up beforehand, I'd at least wrap some baling wire on the bike to use later- just in case. And just to re-emphasize: if it's not a major pain, remove the ECU, not just unplug it. smoother- it just might be. The fact that it cracked indicates to me that it was under some stress. Of course welding exhaust tabs used to be a 2-stroke ritual, as you well know. have a blast.
I ran my 300 for 6 months with no bottom tab jus a big old zip tie onto the frame. Finally got the mount fixed but it was fine without it pipe didn't hit rads or move too much.
i work at a plant where we build carriers and wreckers..so LOTS of welding on truck chassis fairly large MIG welders. we disconnect the negative leads only from the batteries and keep the ground lead right where we are working. there is usually a sticker on the truck frame instructing this practice. of course if its right there unplug any electrical stuff. certainly wont hurt being careful. have welded on well over a hundred trucks with no components disconnected, just negative battery leads.
Just make sure after you get it fixed to replace the exhaust flange O-rings. That's where the added vibration wears