Webbie, you have two standard oversizes to go if you manage to wear out the 76 mm. bore, and 77.5 is an option after that. Just how long and hard do ya plan to beat on that poor bike?!
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Gary, Facts and figures to support a statement but your forgetting one simple fact....................Again..........If a novice buys your pistons, takes them to a machinist, (who claims to be able to do the job), and said novice relies on said tradesman to do the job properly, there is always a chance that the machinist makes a error or is not as proficient as he claims. or takes to big a slice off the bore, maybe to save time and make more profit...................and the sleeve is warped. That machinist is going to blame every thing except him
Now a novice doesn't have the contacts you have cultivated over the years...............So..............just how is a comment, "you need a new bore guy", (if you say this to Jack I'm sure you would say it to a novice), really going to help.
IMHO, (in my honest opinion), is an opinion honestly stated but not necessarily a closed one. Don't assume it is.
Grizld1. Again it was a devils advocate situation i was writing from, and using my situation as a bike owner not mechanic, (as an analogy for others) from a novices, (not necessarily me), point of view, to question why, or who, can i believe when conflicting statements are floated by reputable posters..
I know you from the carb guide, being on here, your long time association with the 650Society and the 650 Garage, so please don't think i am questioning your riding or mechanical experience on the XS650.
Now a novice doesn't have the contacts you have cultivated over the years...............So..............just how is a comment, "you need a new bore guy", (if you say this to Jack I'm sure you would say it to a novice), really going to help.
IMHO, (in my honest opinion), is an opinion honestly stated but not necessarily a closed one. Don't assume it is.
Grizld1. Again it was a devils advocate situation i was writing from, and using my situation as a bike owner not mechanic, (as an analogy for others) from a novices, (not necessarily me), point of view, to question why, or who, can i believe when conflicting statements are floated by reputable posters..
I know you from the carb guide, being on here, your long time association with the 650Society and the 650 Garage, so please don't think i am questioning your riding or mechanical experience on the XS650.
Skull, this whole thing started when a guy who didn't know what he was talking about made blanket generalizations about forged pistons and had to be told that it ain't necessarily so. Then my good friend Jack muddied the water by claiming that not only Gary Hoos and Yrs. Truly but also the late Sheldon Thuet and JE's tech department didn't know what they were doing. Evidence? Well, some unnamed guy said he had his jugs bored for .006" PTW clearance with JE pistons. Then the flap about cylinder wall thickness; there's some doubt in my mind about what Jack meant. I think he meant that 78 mm. is too far on standard liners, but Gary read him to mean that 77.5 is problematic. If somebody has issues with cylinders bored to 77.5, yeah, they need to get away from that clapped-out boring bar in the motorcycle shop that gets used 4 times a year.
A novice can decide for himself who to listen to, and he can study, do, and increase his knowledge and experience. He can also spend some time making contacts in his local area and finding out who has a decent reputation and who doesn't. The novice is not going to get the sum of all knowledge handed to him on a plate on an Internet forum; he has things to learn, mistakes to make, and dues to pay.
Anyhow, I hope you collected the retainer for your advocacy up front--that client of yours has a pretty bad rep when it comes to paying his bills!
A novice can decide for himself who to listen to, and he can study, do, and increase his knowledge and experience. He can also spend some time making contacts in his local area and finding out who has a decent reputation and who doesn't. The novice is not going to get the sum of all knowledge handed to him on a plate on an Internet forum; he has things to learn, mistakes to make, and dues to pay.
Anyhow, I hope you collected the retainer for your advocacy up front--that client of yours has a pretty bad rep when it comes to paying his bills!
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webbie
XS650 Member
Oh I'd prefer not to do this again anytime soon, but if I keep the bike long enough, that eventuality will roll around, no?
Okay, so my pistons are sorted out. I'll ask the machinist to put a chamfer on the bottoms of the barrels after the bore.
In the meantime, I'm moving on to the valves. Upon initial inspection, they look like they could use a lapping, though there are some pretty heavy carbon deposits making it hard to tell for sure. So that's next up...
Many good points, I We have done so many over last 10 my best count is sold over 300 probably closer to 500 and bore 15 to 20 a year. I know not every machine shop do good work, so there is always room for error. Maybe that would be a good thread to start " quality Machine shops in your area". or "where to get your cylinders bored". They can also screw up any bore size. Nothing against Jack , it is just that we have done so many. Gary
Jack .No not do that it was brought to my attention that you were talking 78mm not 77.5mm we do. We have never gone that far so you may be right. I do not know. It probably would be getting pretty thin. Gary
webbie
XS650 Member
I've got a left inlet valve (pictured) with some moderate pitting on the stem. The rest are all pretty good. The rocker arms have minor pitting on all four contact surfaces. Any good way to clean those surfaces up, or could they be put back into service as is? The pictures valve is definitely the most severely pitted.
Those can and should be cleaned up. Standard automotive machine shop practice, but limit surface regrind to 0.005", to preserve the stellite surface.
More info in these:
http://www.xs650.com/threads/valve-goes-in-and-out-of-adjustment-randomly.28536/
http://www.xs650.com/threads/xs650-valve-and-clutch-adjusters-resurfacing.41639/
More info in these:
http://www.xs650.com/threads/valve-goes-in-and-out-of-adjustment-randomly.28536/
http://www.xs650.com/threads/xs650-valve-and-clutch-adjusters-resurfacing.41639/
webbie
XS650 Member
After 6 months of basket-case status for my bike and a move to a new state, I'm finally resuming my rebuild. Hoping to finish buttoning the engine up before the end of may. A couple of questions have come up.
Question 1: Camshaft bearings: how picky to I need to be about the feel? Visual inspection reveals zero pitting, but after cleaning them out (simple green soak, followed by brakleen), there's an intermittent rough spot when I spin them dry. It crops up most readily when I put any side-load on them. I know from reading that they're pretty robust bearings, and they spun pretty smoothly before I cleaned and dried them. Am I asking too much of them to spin smoothly when dry, and they're probably fine? Or should I play it safe and replace them?
Question 2: Gasket surfaces. Oh my god, I'm driving myself nuts trying to clean the base gasket surface on the crankcase... So far, I've stuck to the CRC gasket remover goo, brake cleaner, rags, and plastic razor blades. It's about as clean as I can get it with these tools, but I'm not sure it's enough. The residue that's left doesn't catch a fingernail, but it feels a little rough. Plastic blades do nothing, even after soaking the spot overnight with gasket remover.
I've cleaned up other such surfaces with a honing stone and a light touch, but I want to keep any grit out of the crankcase since I have no plans to split it.
Any other hidden secrets for cleaning up this surface?
Question 1: Camshaft bearings: how picky to I need to be about the feel? Visual inspection reveals zero pitting, but after cleaning them out (simple green soak, followed by brakleen), there's an intermittent rough spot when I spin them dry. It crops up most readily when I put any side-load on them. I know from reading that they're pretty robust bearings, and they spun pretty smoothly before I cleaned and dried them. Am I asking too much of them to spin smoothly when dry, and they're probably fine? Or should I play it safe and replace them?
Question 2: Gasket surfaces. Oh my god, I'm driving myself nuts trying to clean the base gasket surface on the crankcase... So far, I've stuck to the CRC gasket remover goo, brake cleaner, rags, and plastic razor blades. It's about as clean as I can get it with these tools, but I'm not sure it's enough. The residue that's left doesn't catch a fingernail, but it feels a little rough. Plastic blades do nothing, even after soaking the spot overnight with gasket remover.
I've cleaned up other such surfaces with a honing stone and a light touch, but I want to keep any grit out of the crankcase since I have no plans to split it.
Any other hidden secrets for cleaning up this surface?
I use paint stripper for all my old gasket removal. It's probably much like that gasket remover you have, just a more heavy duty version. Maybe you do have all the gasket off. What you're left with may be corrosion on the aluminum. You may need to scrape and smooth that out with a small knife. Don't "shave" into the surface like you're whittling a stick, hold the knife blade about at a right angle to the surface and scrape.
webbie
XS650 Member
Got it. Yeah, it seems to be corrosion more than gasket material. I have some aircraft stripper I could try as well. That's a good tip on the knife. I'm guessing I want something more substantial than a razor blade. I'll give that a (careful) try if the stripper doesn't take any more crud off.
meanEG
XS650 Enthusiast
Use your gasket remover and a pan scrubbing pad. You can get stainless steel ones at the grocery store. They look like steel wool on crack. These are the most effective things have ever used.
webbie
XS650 Member
Are these the sort you're referring to?
I assumed steel wool was too harsh for the aluminum gasket surface. Good to hear I may be wrong! On that topic, what are your thoughts regarding brass wool?
meanEG
XS650 Enthusiast
I have used both with same results. I use which ever I find first in the shop. I have not seen the stainless gouge the aluminum. Theory says the brass or copper would be safer.
Webbie, should have posted this before, but if you haven't had your cylinders bored yet, there's no need to have a new chamfer cut at bottom. Even with cylinders bored to 77.5 mm., there's plenty of the original chamfer left.
webbie
XS650 Member
Actually, I got them bored back in August. I just asked the machine shop to ensure that there was some chamfer remaining. I don't know how much they actually cut, but they didn't charge me extra for any chamfer, so I didn't worry too much about it.
