Crosshatch???

[Kara25]

Hi.!Got a set of used cylinders and pistons that came numbered and with all the rings intact. After a clean in steaming soap water i can see this. Is that a factory crosshatch?? I am wondering if i can super clean everything and reuse them without honing and re-ringing. Havent measured the bores yet but the parts are supposed to be from a 35.000 kms motor. Bores&Pistons by Geo 25, on Flickr Bores&Pistons by Geo 25, on Flickr Bores&Pistons by Geo 25, on Flickr Bores&Pistons by Geo 25, on Flickr Bores&Pistons by Geo 25, on Flickr Bores&Pistons by Geo 25, on Flickr Bores&Pistons by Geo 25, on Flickr Bores&Pistons by Geo 25, on Flickr

 

[Kara25]

Bores&Pistons by Geo 25, on Flickr

 

[1978GS750E]

Hone the cylinders and put new rings in it! That way you know what you have in there. (Just my .02)

 

[Suzukian]

You hone for final sizing. If the pistons and rings fit, why would you Hone them anymore. It's a sloppy crosshatch, but it will do what it's supposed to do. Why take off anymore stock, unless the pistons are tight? The ring gap is your only concern, and as long as that's fine, those pistons should be tight (not binding tight, but drop through slowly tight) going up and down those bores (dry) till they break in. I would not hone unless you have a tight piston. Maybe you should read up on honing to find out for yourself. Also, make sure you assembly the motor with high quality assembly lube on everything in there, rings, pistons, bores, bearings, EVERYTHING. It will ensure a well lubricated start up. I would consider removing the rings on the pistons, and glass bead blasting them. You don't want to put them in there with that carbon on there.

 

[rphillips]

Decisions, decisions... I got a used set of 1148 sleeves, pistons, and rings from a buddy... Bolted them in my 1100 and all was good, no problems at all.. That being said, I couldn't recommend that to others. I agree with him ^^^ new rings and honing will be great insurance you won't have problems. No way to tell if those marks are OEM or been done later, or I can't anyway.

 

[Kara25]

Guys thanks for the info Suzukian yeap lots of permatex assembly lube for sure. I have a 550 top end rebuild/refresh under my belt from 3 years ago so i am not panicking for the assembly stage i like the OCD nature of supercleaning and lubricating everything. The measurements/catasrophic failures of parts upon assembly smoking like a chimney for example is what worries me.Got excited when opened the package its not everyday you buy a 40 year old used motorcycle part and think you can get away without paying 300 Euros just for piston rings!S o the only way to tell if they can be re-used is to measure ring end gap eh? Pistons are already soaking in Kero-acetone mix..

 

[Grimly]

Have you measured the bores and pistons?

Measuring the ring gap will only tell you about wear, but in no way tells you anything about the state of the rings, and their history.
Rings can get overheated and fail, then or later.
Motorcycle owners /users tend to give their engines a harder work-out than most car users, and wearing parts that fly up and down at considerable speed take the brunt of that.
Re-using old rings is a foolish saving when they can be got from Cruzinimage relatively cheaply.
Don't listen to bad advice.
https://www.cruzinimage.net/2017/08/30/suzuki-gs650-62mm-standard-piston-rings-set-4-rings-include/

 

[zed1015]

The honing below the stroke of the rings is original but the coarser makings on the actual bore and overlap look to have been done recently by a blind man and some sandpaper.
If they were mine i would have them correcty plateau honed if limits allow and fit new rings.

 

[1978GS750E]

"Re-using old rings is a foolish saving when they can be got from Cruzinimage relatively cheaply.
Don't listen to bad advice.​"


"If they were mine i would have them correcty plateau honed if limits allow and fit new rings.​"

What they said!:clap:

 

[Kara25]

Tomorrow will be the measurement of the bores hope there is no need to go overbore. Unfortunately cruizingimage is no option for me bcs i live in europe greece. Import tax will take the 4 sets of rings from them to the same amount as the OEM suzuki ones...Grimly thought so.there was no way that the factory crosshatch will look that rough zed1015

 

[Suzukian]

We have to be aware that people in certain parts of the world do not have the options we have. That being said, a little lube, and seeing how the pistons drop through the bores will tell you if they are tight, or way too lose. I don't know how many miles are on that engine, it would be good to know. Once you have matched a piston with a bore, wipe it dry, and with your hand, slide the piston up and down the bore to see if there is any wobbling. Do this relative to where the piston pins line up on the connecting rods. If the pistons slap around, the bike you put together may work, but will be on borrowed time. In your situation you can only do what you can do. Try and line up parts that fit best. If you get the bike running, be gentle with it, and you will get much us out of it. Times are hard in Greece. I commend you for making do with what you have and having such a good nature about it.

If the piston rings are too tight (oversized), you can always grind off the ends. You can't add metal though.

 

[Kara25]

Suzukian Thats the nature of the game if you live in europe not only you have to hunt down parts from the continent but also from inside the EZ otherwise strict import taxes shoot the total amount of parts to crazy amounts of money. Unfortunately you hit it on the spot there is not the vast amount of suppliers here like in the states were you can practically build a motor from scratch with NOS parts and still be on a reasonable bugdet for o a total rebuild. Main concern is not having a smoker on my hands. I dont mind buying OEM miscalenous stuff for my build to around 400$ but just 300 for the rings sure stings.! Gonna measure everything tomorrow and hope at least i can use the STD pistons. The mileage of the bike was 35.000kms according to seller meaning 21747 miles!

 

[Grimly]

Thats the nature of the game if you live in europe not only you have to hunt down parts from the continent but also from inside the EZ otherwise strict import taxes shoot the total amount of parts to crazy amounts of money.

You might have missed that I'm in the EU, too.
I expect that $40 for the rings, plus shipping, plus taxes will turn into well under €100 by the time they get here.
Last set of GS850 rings I bought from Cruzinimage were about that in total - a massive difference from OEM prices.

 

[Suzukian]

You two should be able to have a better conversation on sourcing. Kara25​ it seems you know enough about motors to make an intelligent decision. I wish you the best of luck, and hope Grimly​ can help you on sourcing parts.

 

[zuluwiz]

Not sure what you're thinking about that wrist pin, but I definitely would not put that back in there. New wrist pins and top end bearings would be a sure bet for me. I don't know what replacements would cost, but those are gone. in my view.

 

[Kara25]

zuluwiz wrist pins,circlips of course will get replaced the whole project is for a 550/673 conversion so time is not limited my 550 runs very well and i have plenty of other scoots to ride. Just got the top end of a 650g and measuring cleaning and reconticioning everything that they will be put to storage untill i start tearing down the 550. I am not in a hurry to avoid mistakes. Suzukian thanks for your positive contribution sir i really apreciate it.this forum over the years is keeping up as the most famous for vintage UJMs in my opinion thanks to people like you. Reading old posts i cant seem to wonder were are some other members with crazy skills and knowledge that were posting here regulary like Tknet,SuzukiDon,Ray. Only nessism seems to be the timeless eternal guru of this site

 

[Suzukian]

I left this site a very long time ago when a group of people would just savagely attack anything I posted. The Moderators and Admins would do nothing, so I left. I have a forum of 55K people, I am the Admin there. It has nothing to do with motorcycles, but I do know how to run a forum. If a member pisses on another member's leg in my forum, I kick the pisser out. If people have differences of opinions and can discuss them civilly, that's fine. This forum doesn't seem to have Moderators, so people say really snarky little remarks. There are enough decent people, so the balance scale is tipping in favor of staying.

What I mean about the piston pin holes, is to drop the cylinder with thee piston pin holes in the position they would be when the rod is inserted, so you know how the piston fits in relation to it is actually going to be used. You could actually take thin sheets of paper, and measure the gap between the piston and the wall. We have plastic shim stock for that, I don't know if you have some, or have some available. I used to re-cone high end speakers, rewinding the voice coil, and you would use the shins to center the voice coil over the magnet while the glue dried around the new rubber surround seal.Great stuff if you happen to have it.

This stuff from Amazon comes a .001" in., so you can double and triple it up to see how much clearance you have, it's PVC, so it's durable.

 

[Nessism]

Okay, one more opinion...

Chances are very high that your bores and pistons are fine. What I like to do is measure out of round and taper in the cylinder, and as long as it doesn't exceed .0010", you are good. The piston to wall clearance isn't overly critical, unless there is crazy wear, which doesn't appear to be the problem.

Replacing the rings would be first choice. That said, there have been members here that have reused rings before with good results.

Either way, use a bottle brush hone, not a straight hone, to apply a fresh cross-hatch. A bottle brush hone conforms to the shape of the cylinder better than a straight hone. 280 grit is about right for GS engines.

I'd soak the pistons in carb dip, to soften the carbon. A wire brush on the crown works well to remove carbon once it's softened, but don't use anything abrasive on the side of the piston or, most importantly, in the ring grooves. There will be carbon in the ring grooves that needs to be removed, so take care of that task.

During assembly, a light coat of engine oil on the cylinder walls and rings is called for. Don't use assembly lube because it's too slippery. We want some friction between the new cross-hatch and the rings, so the rings wear and seat quickly.

Replacing the piston pins is fine, but you might want to measure first. For this, you need a micrometer that reads down to .0001". Many cheap mics won't read that low, so be warned.

For gaskets, OEM is best. In particular, the base gasket.

Of course, go through the head. I like to have the valves ground, and a few thousands removed from the stems. If the seats look clean, lap them to clean, otherwise have someone do a very light cleaning cut to the seats so you have a fresh surface. Don't use a drill motor during lapping. If the seats don't clean up with light pressure on a lapping stick, the seats need to be cut.

 

[Kara25]

Suzukian Nessism first of all gentlemen i wish you a happy new year and to be safe and healthy. Now to the matters at hand. Mr nessism valves are lapped with paying attention and measuring with a digital caliper during the proccess the seat width in case i got too carried away and got over the limit. Seats are clean with a mat silver finish and rid of any black tiny dots that were there. The valves are rotating freely on their seats no obstructions. the head is fully cleaned and blown with compressed air + all chambers passed the leak test with gas poured in them and left upside down so i think i am good i will wait for 8 OEM valve seals to reasemble the head and be done with it. Now the barrels. I will take them to a machinist friend to double check my measurements ,hone and put new STD OEM rings. I thought about it and this bike is my baby i spent in the course of 4 years more than 7000€ in upgrades parts etc so not the time now to be stingy if i am gonna make it work as a 673. For the history. I measured ring end gaps for each cylinder and the biggest feeler i could get throught the ring gap was 0.30mm no more on a limit of 0.70mm by the manual so i assume the barrels are truly from a low mileage motor. Also i took 1 piston stripped it of rings and put it upside down on each barrel inserting feelers beetween the wrist pin hole and cylunder wall on the top position and in the middle. The biggest feeler i could slide on that test was a 0.25mm so again i think i am 100% covered with a hone + new STD rings. Now for the pistons. I soaked them in turns i kero/acetone mix and cleaned the tops with a scotchbrite pad by hand there was minimal carbon anyway. As for the ring grooves i used an old piece of piston ring while soaking to soften the gunk and it removed whatever residue was there (minimal). I am moving slow dont want to screw anything up. The biggest obstacle i believe will be the crankcase relieving i detest and i think it will be out of my league to split the cases. I am discussing ideas with my buddy how i can cover the holes and rods to catch as many fillings as possible. Maybe buy a barrel of kerosene also to flush each hole after the procedure with the oil pan removed. Wrist pins and circlips i dont trust them they will all be replaced with new they are cheap enough.12151-67001 is the code for 650 pins 4 of them and peace of mind one thing less to worry about.

 

[rphillips]

I've been trying to keep up, and always eager to learn. Ed just mentioned something I'd been wondering about since post [NODE="4"]Groups[/NODE] He said, We want some friction between the rings and new cross-hatch so the rings wear and seat quickly. That's what I'd always thought, the new cross-hatch made tiny little ridges that the new rings would kind'f rub or, hone down, to perfectly match the new rings. old cross-hatch had "already been rubbed or honed down to fit the old rings". Then post [NODE="4"]Groups[/NODE] said the honing was for final sizing, If the pistons and rings fit, why would you hone them any more? Why take off more stock if the pistons and rings fit right?...