Mechanical/restoration supervision sought

[terbang]

yup, the cylinders were worn out of tolerance, past the just honig stage (4thou out of new)

With the pistons it's usually the ring groves that wear out and the bore that wears. The body of the piston will outlast the rest. If yer bore is out of tolerance than bore it oversize which will fix any piston doubts you may have as well.

[psyguy]

With the pistons it's usually the ring groves that wear out and the bore that wears. The body of the piston will outlast the rest. If yer bore is out of tolerance than bore it oversize which will fix any piston doubts you may have as well.

yup, the cylinder bores were worn out of tolerance, past the just honing stage (4 thou out of new)
so, i'm going for oversizing
ps. it's also true i'm known for spending money on new parts even when that's not absolutely necessary

[peasea]

I didn't think they looked too bad. The discolouration is blowby, a certain amoiunt is inevitable after a high mileage. The scoring looks like oil changes were not too regular in the past. As Mr Terbang says, an aircooled motor has to have fairly large clearances, and stuff will rattle and tattle.

Scoring can also be caused by ingestion of particles through ill-fitting (or absent) air filters. Always run an air filter and make sure it fits snugly on both sides of the airbox. Something many people overlook is ring gap. If the ring grooves are worn and you get 'ring flutter' you lose performance, use oil and generally flog a dead horse.

[psyguy]

Scoring can also be caused by ingestion of particles through ill-fitting (or absent) air filters. Always run an air filter and make sure it fits snugly on both sides of the airbox. Something many people overlook is ring gap. If the ring grooves are worn and you get 'ring flutter' you lose performance, use oil and generally flog a dead horse.

guys thanks for your enthusiasm and all the replies, i'm learning so much!

[terbang]

it's also true i'm known for spending money on new parts even when that's not absolutely necessary

Dunno what there is available for an 850 but last time I did a bore on an 1100 I went the wiseco 1150 kit. Worked out fine too at a reasonable price. These guys here at http://www.gszone.biz/ have a lot of stuff for GSes as well.

[psyguy]

Dunno what there is available for an 850 but last time I did a bore on an 1100 I went the wiseco 1150 kit. Worked out fine too at a reasonable price. These guys here at http://www.gszone.biz/ have a lot of stuff for GSes as well.

hey, thanks for the link. i surfed the net a lot but missed this site?!
i've ordered 1.0 oversize pistons/rings from suzuki (through "alpha sports")
cheers

[psyguy]

Wade Automotive Reconditioners also have vapor blasting facilities.
It was $100 to do a big block Guzzi motor, sump and timing cover. 30 years old and it looks brand new- inside and out.
Jap alloy must be different because I leave the Guzzi motors and 'boxs bare no problems.

i went to wade automotive, penrose to have them vapour blast - refinish - one part that still had some dirt in between the fins

their finish is nowhere near that of performance transmissions, pukekohe (where i had the whole engine done)

the part is definitely clean but with no shine. the machine at pukekohe leaves an atractive silky smooth shiny finish (as per the pickies i posted)

so, if anyone's thinking of this process, i definitely recommend go to pukekohe (well, at least for suzuki alloy from the eighties...)

[Alive]

I am definately going to have to bring the xj900 around to see you...

I'm very interested in the work you are doing as I have some XJ650 motors to rebuild and I'm liking the look of what you've done...

Good job

[psyguy]

I am definately going to have to bring the xj900 around to see you...

I'm very interested in the work you are doing as I have some XJ650 motors to rebuild and I'm liking the look of what you've done...

Good job

yeah, very keen to see your bike and meet you, and we can celebrate over a beer or two

[psyguy]

got the long expected parcel yesterday, wanted to hug and kiss the postman...

opened the package
inside, among the smaller pieces, TWO larger boxes
suspicious...
if those TWO boxes aren't the pistons, then where are they?!
if those TWO boxes ARE the pistons, where the hell are the other TWO?! i ordered FOUR!

sent a query to the company i got the parts from
they say i was sent only TWO pistons and not four as those were the last two pistons they had and have no more...
also say that they informed me about that prior to sending, which they hadn't (and i have all our correspondence saved)...

how do i feel?



on a positive note though, check out those peanut m&m's they sent me...

[jonbuoy]

Like being kid again at christmas eh?

[psyguy]

Like being kid again at christmas eh?

yeah, maybe like a kid that got HALF his present!

[jonbuoy]

That is annoying - It took me a while to find someone that could supply everything in one hit without paying for extra freight. You find a source for those last two pistons?

[psyguy]

hey people!

any ideas on where to buy a couple of oversized pistons 1.0 (1980 suzuki gs850)?

i've emailed a few places and checked a few websites already

so far, with negative results:

• alpha-sports
• bike bandit
• old bike barn
• suziparts au
• parts n more
• z1 enterprises
• gs zone

pending:

• anderson vintage parts
• crooks suzuki
• flat-out motorcycles
• vintage suzuki
• e-bay
• tiaro wreckers
• buckets n bits

any suggestions highly appreciated

[Ixion]

Try Robinson's Foundry (odd name, but it's a bike site) in the UK. They have a lot of early 4cylinder Suzuki stuff. I'd have said that if Suziparts don't have it's looking grim, though maybe your bike is a bit young for them.

EDIT. Just checked Robinsons, for part no 12111-45110-100 (S/B 1.0 OS Piston for 1980 GS850G , still listed by Suzuki, BTW) , they reckon they have them in stock . Bloody dear though, 38 quid each.

Their website is shit BTW, until you know the trick you can never get anything to come up when you search.