What have you done to your XS today?

Believe me, Bob, if you buy yourself an XS650 you'll have something to say.


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I've been pretty satisfied with the stock pipes on my '82 Special which I use to cruise the Catskill Mountains, especially because it's rather quiet; the small town locals smile and wave to me when I come through, but not so much as the raucous Harleys invade their space.

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However, lately I've been yearning for a bit more sound and performance, so I sprung for the 1.5 headers and Commando Megaphone mufflers at XS650.com. Nice price.

The removal and fitting of the new system was straight-forward. Before installing the headers I sprayed 2000 degree ceramic coating inside, 2 coats, dried quickly with a hairdryer.

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Once installed, I did the obligatory heat-cool-heat-cool-heat-cool cycles (to fully cure the ceramic) which took 140 minutes.
Then went out for an hour ride in the sunny, lower 60's afternoon.

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I had already bumped up the mains one step when I got the bike. It ran perfectly with the new system, and now I've got a slightly louder and throaty exhaust note which I like. The performance bump is most noticeable to me in the latter half of the performance curve; it doesn't feel as "held back".

After an hour of assertive riding, the headers have turned only a faint golden color in the first 10".

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Then it was time for what might be my last-of-the-season mint chip ice cream cone at the Byrne Dairy in Lafayette.
Yum.

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This pic looks like a big nose bloke with nice green hair.





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My XS especially loses front tire pressure faster than the other scooters, more like a bicycle tire... (today I check air pressures)... this condition is stable as to rates...over several years... and of course is faster in the spoke-wheels, but nonuniform. The XS is far worse than the Harleys. I studied about this problem in bicycles...and got as far as buna is less porous than latex inner-tube material. I strongly suspect the XS front tube is of a material the is most porous.

This invites, then, the idea of sizing material to reduce porosity, thence loss of gas. One form of sizing that seems interesting would be to use GOTA (gas other than air) with a nice fat molecule that can't pass through. R134 for example. I am curious about chemical compatibility and pressure temperature gradients. I have noted that some racing is done with GOTA.

Ok, remarks?

Best!
 
I bought a set of tires from a friends son who just bought a tire shop being told I would get a discount
I think I got a discount for the tires but "Mike you really should have us put nitrogen instead of air in your tires they'll hold pressure longer and if you need to bump up the pressure when your out of town you can use just regular air and it won't be problem"
With the upcharge for the nitrogen I didn't get a discount instead it was quite a bit more
"Hey Mike better change out that summer air it's getting cold out":cautious:
 
I bought a set of tires from a friends son who just bought a tire shop being told I would get a discount
I think I got a discount for the tires but "Mike you really should have us put nitrogen instead of air in your tires they'll hold pressure longer and if you need to bump up the pressure when your out of town you can use just regular air and it won't be problem"
With the upcharge for the nitrogen I didn't get a discount instead it was quite a bit more
"Hey Mike better change out that summer air it's getting cold out":cautious:
I have heard of the N2 bit. Also He...it's lossy as can be, but it transfers heat really well...racing stuff, formula cars and a cat I knew in the 70's.

I suppose I'll get some R134a and try it on a pair (control and test tires) on a bicycle.... I wonder if the pressure might rise too much when heated, and also if the organic fluid (it is) might also act to turn inner-tube to glue or mess...and if buna and latex might not have very different reactions.
Ah dunno. Just hoped somebody does. Thanks! 40N
 
I bought a set of tires from a friends son who just bought a tire shop being told I would get a discount
I think I got a discount for the tires but "Mike you really should have us put nitrogen instead of air in your tires they'll hold pressure longer and if you need to bump up the pressure when your out of town you can use just regular air and it won't be problem"
With the upcharge for the nitrogen I didn't get a discount instead it was quite a bit more
"Hey Mike better change out that summer air it's getting cold out":cautious:
I worked for an IMSA and Grand-Am race team for decades. I was their paint and body guy at home, and the tire guy on the road. Nitrogen is great on the race track as it contains no moisture and the tires do not "grow" as much which allows for a more consistent tire from hot to cold. On a street vehicle you will never get the tires hot enough for it to be of any benefit. You can put air, nitrogen helium anything you want in a tire, if there's a place for it to leak, it will find it. BTW, the race team I worked for was also owned by a M-B, Porsche, Lexus dealership, and they made a nice chunk of money "preloading " every new car with nitrogen.
 
He is almost impossible to contain, as it's an atomic gas, very small. We worked with He as coolant fluid in an experimental nuke longtimeago. I am sure you can put it in a tire, and sure it will leak out faster than any other gas. Spendy too. It is a very good heat transfer fluid, in principle. (So is H2, and that's easier to contain, but it has problem too) We never managed the leaks... And there were big problems running the fans via de-ionized high pressure water turbines...hot stuff yaknow.

My interest is in the least fast leaking gas that behaves well...P/T gradient similar to air. Now that I think on it NH3 might be a nice gas... But I'll do the freon experiment first, since the stuff is cheap and safe and probably won't melt the rubber, or whatever "elastometricstuff" the tube happens to be of.

It's just an irritating very very slow leak...10 psi in 30 days...and the curiosity of the matter. My scooter tires seldom get hotter than the street in shade... But some gasses expand more than other as temperature rises. We recall the Good Ol' Boys and the cop car chase with exploding tires from the Blues Brothers...

Connecting can of 134 with take some plumbing, and it calls for purge too...we'll see.

Think science fair with beers...
Best! 40N
 
I don't buy into the nitrogen for my tires. Another way for them to squeeze a few more nickels out of my cheap ass. Good 'ol O2 been working just fine for many years.
You are absolutely correct, IMHO. I'm not really all that frugal, I just haven't been convinced that it matters in a street vehicle.
 
Now that's amazing, 78 percent nitrogen, and yet if we make that 100 percent we die, I read sometime ago it was suggested that the states with capital punishment use nitrogen as they were having problems procuring the stuff they normally use. It's supposed to be more 'humane', according to exit international.
 
Is it just me? I fail to grasp the relevance of nitrogen as a pathogen or Swiss suicide pods to the question What have you done to your XS today? I mean, when I was dealing with the known unknowns and unknown unknowns of rescuing Miss November from the misadventures inflicted by (unknown) POs I felt a wide range of emotions - surprise, annoyance, incredulity, trepidation, WTF but I never came close to feeling like bringing my earthly perambulations to a swift end.
 
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