Modern Vespa

How hot does the coupling get?

http://www.adlinsulflex.com/heat-resistant-tapes/fiberflect-tape

There's a guy here in Sacramento looking to sell his t-max... been trying for a year.

yeah, I really don't need another bike. Seriously. I really, really don't.

Oh... but it's so fun to pile on!

I think exhausts get up over 1,000 degrees. I seem to remember that an oxygen sensor needs to get to 600 degrees just to begin functioning.

(this is all based on hazy memory...)

http://www.adlinsulflex.com/firesleeve/silicaflex-sleeve

I dunno. I like Randy Turkman's modification, and it has a 30,000 mile history behind it, and counting.

are those two different pipes?
a bit o.t but...is there any aftermarket pipe out there that is as quiet as the stock pipe? for those who dont't like the growl...but want a longer lasting pipe....

Oh don't give up on the brand Jess! I'm bummed about my fuel injected LX too, but you are in the unique position of owning perhaps the most well known forum "all about the brand" today!

Perhaps you could start a poll to find out if there are sufficient numbers of people experiencing the same problem to warrant Piaggio announcing a voluntary factory recall and perhaps even initiating a redesign. You may be pleasantly surprised! So far, I have found Piaggio to be very responsive to my particular problem. They are doing what they can to help solve it for me.

Is this a 250 VESPA problem only. How about BV or MP3 250 (or the 500 ones), I haven't read about this much problems, if any, with them and the engine is basically the same but the pipe is different.

The "plate" connecting the rear wheel to the engine seems quite slender on the Vespa so could there be any extra movement there putting additional strain on the exhaust

I believe they are the same except for the addition of the chrome tip on the 300 Super pipe.

at lower speeds and idle the LV isn't much louder than the stock exhaust, and it's got a deep throaty note to it rather than an annoying whine. if you like, it can bark quite loud when you hit the throttle but it can also be surprisingly quiet when you want it to be. the LV has no graphite collar and it takes about 20 minutes to fit. a handful of people have had problems with them cracking at the header, but the majority of owners seem happy.

Here you go: http://www.semenoff.org/vespa/GTSExhaust.pdf

Jess,

I don't understand why Piaggio doesn't use a Stainless Steel Flex Coupler?



http://www.exhaustdepot.net/misflexseco2.html

They will make custom ones, maybe someone should try them out.

Wayne B

OK, how do I post an image so it will show up in the post?

The way you did it would work if the URL had an extension identifying itself as an image (eg .jpg or .gif)

Ok, thanks

Wayne B

I don't think that the supports are properly designed to work
if you put in a more flexible coupling

Probably the exhaust system would just break somewhere else

IMO, the biggest virtue of Piaggo's stock design
is that the exhaust system does tend to break at it's cheapest part
(just a bit too often for my taste)

Randy's solution is definitely worthwhile, and is one of my preferred solutions as well. I've welded up two exhausts so far, although neither one looked nearly as clean as Randy's professionally-welded version.

The only real problem with the welded-one-piece is that the pipe leading from the head to the can tends to deform a bit over time, making it harder to put it back on during subsequent tire changes. My experience (and glasseye's as well) is that it shrinks, brining the can closer to the front of the bike.

In glasseye's case, the factory joint between the pipe and the can eventually failed, and produced a perfect 1mm gap between them, all the way around. It broke during (wait for it...) a long, hard ride back from Seattle on a very hot day.

Which happens to be the same day and same trip I blew an exhaust gasket for only the second or third time.

Of the two exhausts I've welded up, one fell off the bike (after being sold to someone else) and was destroyed by passing cars. The other one was given to the same individual to replace the first one.

As far as I know, this problem is specific to the GTS / GTV line. The MP3 and BV use a different exhaust system.

It would work. None of the weight of the exhaust can (which is quite heavy) is supported by the header pipe, it's all carried by the swingarm plate.

I suppose in one sense the OEM part actually does work. If you look at the graphite sleeve as a "consumable" the way Piaggio does, you just replace it occasionally and move on. The sleeve does allow the two parts to expand and contract without metal fatigue or strain on the bolts, and it is possible to replace one out in the wilderness fairly quickly if you happen to have one with you.

If Piaggio supplied them for say, $10 then I could see them as a consumable a little easier, something you do every other oil change.

I wonder if anyone else supplies graphite sleeves (in the same way you can buy standard bearings) at a fraction of Piaggio's price?

Cost, probably.

I would hope so, I've paid CDN$55.00 per unit.
Recently bought 2 - one to replace the bronze bushing and one as a spare.
I had tried the bronze bushing (CDN$72.50) but sheared an exhaust bolt within 500km.

This is the 3rd graphite replacement in 19k kms. The first 2 failed due to removal and re-installation of the muffler for tire changes and pad replacements.
At these prices, it wouldn't take long to pay for a new scoot.

Yes, exactly. My Super has roughly the same mileage.

Took it for an 300 mile round trip to the Isle of Wight on a nice sunny day.

Boom! It starts to die on the way there, and by the time I was riding it back, it was getting to Harley levels of throatiness.

Taking collar out to put on the LV instead, the collar looked shagged to bits. I should have taken a photo of it!

I'm debating LV or welding at this point. Finding a piece of flex pipe that would fit would be nice, although I'm not entirely sure how well that would hold up, either.

You are correct things do shift forward a bit. I enlarged the mounting holes on the exhaust a tiny amount and (so far) solved the problem of having the exhaust not line up with the bolts on the swing arm plate. I guess I need to just go get LV pipe!!

Yeah, I had to do the same thing. Glad to know it's somewhat consistent, at least. I dunno... 30,000 miles on that exhaust is pretty good.

I found that spreading the muffler pipe and inserting the graphite bearing fully into the muffler pipe and then installing to the exhaust pipe, made a very tight seal. Bolts lined up as well.

Now I can plug the outlet and the engine will stall in 2 - 3 seconds. No leaks - SO FAR.
Previously, there had always been a little exhaust leakage at the joint, even when new.

I also spread the muffler input with a tail pipe expander but I installed the gasket on the header pipe first and then installed the muffler. I also used a small amount of anti-seize paste which may not be necessary; I just felt it would help a bit in sliding the muffler on. I hope the anti-seize past doesn't cause any harm. We shall see. This is the tail pipe expander I used:

http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=37352

The correct way is to install fully into the silencer (muffler), with the graphited end first for the new-style collars[1]. If you install onto the downpipe first you are in danger of it not being fully home in the silencer.

Also insure all traces of the old collar are removed first, and the mating surfaces are spotlessly clean and smooth. This may take some chipping old gunk out and the use of a rounded file or a dremel. Having the surfaces clean and smooth will vastly improve the life of the collar, which is designed to slide on the downpipe to take care of expansion issues. On the 500 engines at least this slide can be 3mm or more. Any tiny bits left proud on the downpipe in particular will cause premature failure.

[1] This end goes into the silencer:



This end is left just poking out towards the engine:

Jess I feel your pain ... i posted about a month ago or so about my gasket blowing. I only have like 2700 miles and no exhaust ever taken off, on mine. The design is piss poor. I do like the flex pipe i saw.

Burgerbob might also be a source of how to succeed. I think his bike is stock, and with the long rides he does, I think it is subjected to similar stress.

For me, the bronze sleeve has worked for approximately 17K miles now. I believe it allows the expansion and shrinkage of whatever wants to while providing sufficient sealing of the system.

I believe proper alignment of the two elements (muffler and header pipe) are key to prevent stress, and proper placement and torque on the clamp is the other key point.

I make it a point to religiously leave the full exhaust in one piece as is when I need to remove it, and to balance it right, to allow it to fit well between the two major ends (header and the three bolts of the muffler), without creating any stress.

So far, it has worked well and I don't see why that should change.

Jess,

They are only $13.78 for the 1.5" one. Can't find a tape measure in my office to measure the pipe. Custom made one can't be more than double the price.

You could even send the pipe you want them to use I bet.

Wayne B

If /when I get my GTS250 back from the water pump seal problem, I know I am going to have this same problem, so I have two spares. I would love to have something like the steel flex solution available to remove the graphite collar all together. Sic's GTS250 did this right after a ride from Sacramento to LA, so it definitely does not like long hard rides. The scoot doesn't mind it, but that bushing doesn't like it. Nothing but sympathy here for those that have had this problem. I know I will unless they come up with a better solution.

Hey, if you want it that badly, I'm sure the Universe will give it to you

I imagine there might be an alternative source. When my mechanic had parts problems on our fleet of Cushman Trucksters we found parts that were adapted by Cushman from other sources. We often found some "consumables" that we perfect replacements and cost 50-200% less!

Just trying to understand why exhaust gaskets are $13 USD in UK and 3 times the cost here?

Group buy anyone?

Buying ten from the UK runs $20 each with shipping.....


http://www.piaggiospares.co.uk/spares/partImage.asp?GPN=826388

I think it's called "whatever the market will bear."

Or "free market capitalism."

Or, just plain gouging.

The tax, tariff it helps balance trade. also the USD is down agaist the euro

That theory doesn't seem to carry on other Vespa/Piaggio products except consumables.....but still an interesting bit of propaganda!

Where did you find a 1.5" one? The website lists a 1.75" coupler, and I haven't found any that are smaller that 1.75". It looks like the pipe on our GT200 is 1.25" OD, does anyone know? I'll measure it when I take it apart to change a tire, but it would be nice to know before. If the pipe is 1.25" and a 1.5" coupler could be found, instead of going custom I would try sleeving the 1.25" up to 1.5".