80G Pilot Jet buggered, air screw plugs

[Bonz]

Looking at MikesXS, a caliper piston is not shown specifically for the XS1100G brakes. Would the piston for an XS650 (1977-84) work?

[GLoweVA]

Looking at the parts fiche, the 77-83 650's used the same caliper assembly as the 78-81 1100's, so that would imply that they have the same sized caliper pistons.
So, It looks like they probably would do the trick. (and at $26.50, not a bad price either IMHO)
http://www.mikesxs.net/product/29-0516.html
I wish I'd had known that 3 weeks ago when I overhauled my calipers on my SG project bike. All 3 of those pistons needed a lot of TLC and some light scrubbing from a scotch bright pad to get them up to par.

[Bonz]

Very nice...

Thanks for the homework on my behalf, I should have looked at the fiche's as well and could have seen that.

[GLoweVA]

I like using the Boats.net site to search fiche(s), once you click on a part number, it pulls up all the other bikes that part number is used on also.
Quite handy in cases like this.

[Bonz]

Looking at Parts n more, they show the dimensions for the 1100 caliper piston to be 41.3 mm, 38 mm. Mikesxs shows 41.3, 38.1 mm. Gotta be the same thing despite the .1 mm difference, based on what you found as well.

Anyone gonna chime in to the contrary before I place an order?

[GLoweVA]

Partsnmore also shows the 650 caliper to have the same dimensions 41.3mm, 38mm and the same part number for each.

[bikerphil]

Another source for caliper pistons....

http://www.hvccycle.com/brake-caliper-pistons.html

[Bonz]

There you have it! Parts ordered...

Thanks bikerphil for that link. Those are sweet, stainless is great. I am "budgeting" this bike back together, so went ahead and got the MikeXS piston for some freight savings with the other parts I ordered. With that said, will stainless be less prone to surface damage of the piston compared to what looks like a chrome coating on the stock pistons?

The 80G is coming together well! Here are a couple pics of the engine after I cleaned it up last weekend after removing the carbs, airbox.






Been cleaning off the wiring harness sheaths all around the bike, lots of dust, but other wise it's been straight forward "detailing" the bike. Forks are fully serviced, all fluids changed, rear caliper has new pads and flushed with fluid, new front tire on the rim ready to go, etc.

A set of Harley mufflers just showed up from my uncle in the midwest off a Road King. He wanted more "Rumble", I call it "NOISE". They are brand new as he replaced them when he bought the bike. They may or may not be a good fit, but for free they are worth a try given the rusted out bottoms on the existing mufflers.

[crazy steve]

Thanks bikerphil for that link. Those are sweet, stainless is great. I am "budgeting" this bike back together, so went ahead and got the MikeXS piston for some freight savings with the other parts I ordered. With that said, will stainless be less prone to surface damage of the piston compared to what looks like a chrome coating on the stock pistons?

The HVC pistons are nice pieces....

The stainless pistons are actually softer than the plated ones, but it's usually rust that causes the damage to the pistons so stop the rust and chances of wear go down....

[Bonz]

Good point, CS.

I found it interesting when disecting the front caliper with the scored piston, that the internal condition of the caliper bore and surface of the piston were good, other than the piston was scored in a band about 1/2" wide with 1/16" long scores.

I should say it like this: When I saw the scoring on the piston, I was puzzled at what could have done it given the overall good condition of everything else. But something got in there and gouged the piston wall, however the caliper bore has no similar damage at all.

[CaptonZap]

Looking at Parts n more, they show the dimensions for the 1100 caliper piston to be 41.3 mm, 38 mm. Mikesxs shows 41.3, 38.1 mm. Gotta be the same thing despite the .1 mm difference, based on what you found as well.

Anyone gonna chime in to the contrary before I place an order?

Jeeze Howard, are you getting sloppy in your old age? That is .0039 inch longer than stock. Goat head, but I'll rub it in when it comes back to bite you.
CZ

[CaptonZap]

I should say it like this: When I saw the scoring on the piston, I was puzzled at what could have done it given the overall good condition of everything else. But something got in there and gouged the piston wall, however the caliper bore has no similar damage at all.

Before you put everything back together, do some careful inspection of the piston bore.
Aluminum is softer that the chrome, and if some sharp abrasive bits got embedded in the aluminum, they would do damage to the chrome while working their way further into the aluminum. They might still be there. Hopefully the PO found them, and removed them, but it wouldn't hurt to make a "feel" test with the sharp edge of a credit card, cut to an appropriate size, and then your finger tip.
CZ

[Bonz]

Can't find any imperfection or embedded particle(s) in the caliper bore. I've had the bore o-ring seal out, cleaned the groove underneath, et al.

Looks like a new piston that is way oversize by .0039" should do the trick. Heh, Heh, Heh...

[GLoweVA]

Vac lines

I noticed in your pic, that the petcock vac lines that normaly come from #2 & 3 are T'd with #1 & 4 respectively. (spot the yellow tubing)



I was wondering to all those guru's out there that there may be something to that.
I'd think that it would balance out the vacuum of those 2 cylinders and thus negate any syncing done prior to pluging them together.
Thoughts?

[CaptonZap]

I was wondering to all those guru's out there that there may be something to that.
I'd think that it would balance out the vacuum of those 2 cylinders and thus negate any syncing done prior to pluging them together.
Thoughts?

YICS, Oops, I mean Yikes!
Now you've done it, you've gone and reinvented a wheel.
CZ