Modern Vespa

Erm...might have happened once or twice...

Actually, you give us the Impression that you always want to be right

only when I am right. its rotten advice to say welding this header is a good idea.

Yeah, but you and others who will remain nameless at this point in time take everything too seriously and you take it as a personal affront when somebody has a different oppinion than your own. I know my abilities and I can tell you without a doubt that I am no Mr. Know-it-all. I never went to College, I never studied Metalergie like Madison or am no Rocket Sientist like jimc, but I can at least say that I have been a learned Mechanic and Welder for 35 years now. You and a few others who will remain nameless at this time need to chill. Keep giving advice though. It does help those who really need it and they and I myself do apprieciate it emmensly. You guys do have pretty good ideas. You just should try to bring it across better with a little Deplomacy. I don't mean just you, but also the other nameless few. I hope I didn't step on anybodies toes writing this, but this perticular discussion seems to be getting out of Hand.

If you search YouTube for "micbergsma mp3" he has several take apart videos that might be helpful.

Yes !

what a BS about not welding used RVS done it many times no problems

Yeah, welding vs new/used is a value proposition rather than a question of whether it possible. A new header is around $100 and taking the pipe to a welder, getting it welded by a professional at exactly the correct angle with a weld that will hold up is going to be about $100 too. Unless you have a TIG welder in your garage, which most of us don't. For something like this, I'd just buy a new one.

Welding should be more then 30 bucks thats what i ask for customers

Agree to disagree. Getting a welder to do a careful job of fixturing, stoppering and flooding the tube with argon, then TIG welding with skill the correct stainless steel -not all shops have all types of stainless steel filler rod- will cost a minimum of $100. It's about an hour job with setup and $100/hr is the going rate for immigrant landscapers around here, let alone skilled craftsmen.

Follow up question: We purchased the exhaust gasket (#26 in the diagram) from scooterparts. The description said it fits a 400 but it looks like it's a slightly different size than the old one. The older one isn't as thick and fits tighter when it's seated in its place in the pipe. Is this normal for a new part?

They wear thin quite quickly. A new gasket is always thicker than an old one that's been in for 1000 miles or so. This is why nipping up the clamp on a regular basis is a wise move, and prolongs the life of the gasket.

Interesting. Thank you!

I'm not so sure they 'wear' thin so quickly, but rather get smooshed.

# 26 folks is the head to pipe gasket not the graphite pipe to muffler bushing.

the new copper gasket should be thicker than the old one as is does squish down thus creating the seal.

did you also get the new studs and copper nuts? highly recommended .

Ah, sorry. I never remove the downpipe - not even when removing the engine, so didn't even consider that gasket!

Once again, many thanks for everyone's advice and help. Merlin will ride again. <3

Yes, they get smooshed when they're installed- makes them thinner and bigger in diameter. That's why I don't re-use the old one; the seal may not be as good with a re-used gasket, and I *hate* taking that header off because the nuts are so hard to get to and I'm willing to spend the extra $5 to make sure I don't have to.

Yeah, we certainly learned THAT on this project! My husband did the bulk of the work but needed my smaller hands to get those nuts threaded. Getting them out was a pain, but getting them back on was brutal. I dropped the danged thing three times before I got it going. Then he wedged the wrench in and ratcheted it down ONE CLICK AT A TIME.

We did use the new gasket, and a new graphite gasket on the other end.

interesting welding in the first part of video. what kind of welder is that? or is it just good technique with tig with heat turned up?
https://www.youtube.com/watch?v=NWNgTlmVXYI
[img]https://www.youtube.com/watch?v=NWNgTlmVXYI[/img]