Potential Group Purchase - Wiseco GS650 741cc pistons

[Tooheys]

Awesome info on break in procedure Etc guys!!

I have some questions though.

how long can I run the engine to sync carbs and sort jetting before it will glaze the cylinders?

Do I get it as close as possible on the bench them sort it after the run in period?

 

[Nessism]

Awesome info on break in procedure Etc guys!!

I have some questions though.

how long can I run the engine to sync carbs and sort jetting before it will glaze the cylinders?

Do I get it as close as possible on the bench them sort it after the run in period?

Put a big fan in front of the engine before doing the vacuum sync job and don't worry about getting it perfect at first. Just get them reasonably close and go ride. You will be fine. Cylinders don't glaze over that easily.

 

[gilldog]

Andy, the pistons arrived safely in the UK, got clobbered with a customs charge though...Very happy with them, thanks for your help

 

[tkent02]

Awesome info on break in procedure Etc guys!!

I have some questions though.

how long can I run the engine to sync carbs and sort jetting before it will glaze the cylinders?

Do I get it as close as possible on the bench them sort it after the run in period?

Smooth idle and perfect synchronization isn't all that important when you're breaking in an engine, since you should be going on and off the throttle anyway. Full open or full closed, synch doesn't matter. Where poor synchronization sucks is trying to ride gently and smoothly in traffic or on a slow or slippery road, or anywhere else you want smooth throttle response at low power.

I'd bench synch them as well as I could and ride the Hell out of it, save the fine tuning for later. Been doing this on my 550/675, after a decent bench synch it ran fairly well anyway, the synch isn't very far off. Got to get into the fine tuning part soon, my jetting is a little bit off but the compression is good.

 

[Chuck78]

Yes, do not mess around with trying to fine-tune the syncnonzation or idle, you are wasting your chances to get the rings broken in properly for the best seal and compression. Do as much research as you can for a good ballpark Main Jet size, needle jets, jet needle and needle clip position, and go out for some medium hard pulls doing the acceleration deceleration thing a dozen times or so. And don't run fancy oil during that break-in period.

 

[Chuck78]

Has anyone got their pistons installed for a torqued mockup of the cylinders to measure for deck height?
I was thinking I'd order 4 or 5 .043" or so thick MLS gaskets from gasketstogo.com, maybe 1 or 2 .030". Old Colt, have you mocked up yours yet?

I'll have to double check on the thicknesses available from gasketstogo.com but I think those guesses were close to what is available.

 

[frankenwabbit]

Chuck78....I'd be up for getting in on a mls gasket once someone here has crunched the numbers.

 

[tkent02]

Cylinder boring, isn't $75 per hole a little steep? I thought it was less....

 

[Ace07]

No. I paid 80 when I got my girlfriends xt350 bored. It's just a 1 cylinder.

 

[Chuck78]

It was $40 per hole 2 or 3 years ago the last time I had one done. I think another place quoted me $130 or 140 for all 4 even. Years ago (3-6yrs?)
Bore tech in Cincinnati OH is a great place nationally known but a bit more $ than M&M Cylinder Head Service that I had do mine

 

[Chuck78]

Is anyone else wanting to get an MLS gasket? It looks like I will only be ordering the minimum order of 5 to get the price break. I was figuring everyone would want a spare or one gasket per set of pistons they ordered minus the five or so NOS Wiseco gaskets that were sourced on ebay

 

[tkent02]

Is anyone else wanting to get an MLS gasket? It looks like I will only be ordering the minimum order of 5 to get the price break. I was figuring everyone would want a spare or one gasket per set of pistons they ordered minus the five or so NOS Wiseco gaskets that were sourced on ebay

I want at least two, maybe a few spares. How much are they?

 

[frankenwabbit]

I'm in for two.

 

[Chuck78]

I believe he quoted me in the $80 range plus shipping for MLS head gaskets if we buy 5 or more.

It's been a minute since I have visited this build of mine, but I believe I was planning to order head gaskets around .043 inch thickness at least for myself.

Colt, have you nipped your cylinder down to the case yet to measure your piston-in-hole TDC deck height? What is your preference on thickness?



I've got a bit of house rehab to do Nov-Dec but the rest of the winter is dedicated to motorcycle projects all the way, & this 740cc GS550 is top of the list... Especially because I have to get the wife on something (THIS 740cc GS550) that's about 200x better than that piece of $#!? '86 Hardley-Goeserson FXR 1337cc 58hp (when new/tuned properly) / 600lb / almost rigid rear end / super saggy front end / no brake having / 99mph top speed (when new/tuned) / old retired guy turd cruiser that she bought... Aaaarrrggghhhh....

 

[tkent02]

I've got a bit of house rehab to do Nov-Dec but the rest of the winter is dedicated to motorcycle projects all the way, & this 740cc GS550 is top of the list... Especially because I have to get the wife on something (THIS 740cc GS550) that's about 200x better than that piece of $#!? '86 Hardley-Goeserson FXR 1337cc 58hp (when new/tuned properly) / 600lb / almost rigid rear end / super saggy front end / no brake having / 99mph top speed (when new/tuned) / old retired guy turd cruiser that she bought... Aaaarrrggghhhh....

Tell us how you really feel.

 

[Ace07]

Hey chuck do you know what the next price break is? I am in for 2 gaskets for now.

hey does anyone know how much it should cost to get my head redone? I found this service on eBay, and I am not sure if it is a good deal or not.

http://m.ebay.com/itm/231865125106

 

[Chuck78]

Dan Schumann does excellent work (ebay guy),
Locally at the real good head shop it runs about $240 for a Serdi machine valve job plus $80 for resurfacing the head gasket surface. Valve guides & replacement not included in the $240. Another shop does it a good bit cheaper but not with a Serdi machine, just standard 3 angle valve job seat cutting tools. The Serdi is a smoother transition than a 3 angle job and computer controlled to cut them all to the depth of the deepest seat for uniformity in chamber volume and cranking compression.

 

[Chuck78]

Ya know what when I had my 650 head done, I recall the factory manual showing that due to the improved port design, it basically got only a 2 angle valve job. Raised intake port runners for more direct air/fuel flow into chamber. If I recall correctly. I remember seeing seat angle specs in a factory manual or clymers.

 

[Chuck78]

As far as gaskets, that gets us at least 11. Quantity of 1 to 4 gaskets are $120 each if I recall, 5+ are $80-something each. I don't believe there is a further price break but I can inquire if interest puts us up there in numbers more.

Anyone need 650 top ends still? There's another 650 at the local yard now. 1 or 2 others but I think they're staying complete/projects. Several 550's too.

I'm torn between taking the blown up 77 gs550 kicker engine (all new used bottom end from junkyard since wife ran 'er outta oil many times cross country - & then bought a Harley in Minneapolis that left her stranded in Cali!!!) and doing my experiment:
GS650 cylinders bored for GS750 pistons (740cc hemi) & 80-82 550 head with gs400 boot spacers & vm28 carbs...
OR
Just slap another 650 top end on it, have it as a spare... I have new 650 rings still, pistons, nice honed good std bore cylinder.
Heck the gs750 pistons at 740cc and substantially milled cylinder head (more compression) sounds more adventurous...

I've got 2 extra sets of Wiseco k740's but one I bought with a friend in mind who didn't have the cash, he hopes to buy them off me this next season. The other as a spare or if I build a 650E or another 550/650 maybe for myself

 

[tkent02]

GS650 cylinders bored for GS750 pistons (740cc hemi) & 80-82 550 head with gs400 boot spacers & vm28 carbs...

Hmmm, with the 650 pistons we sere stuck with 650 heads, how do these 740 pistons fit the 550 head's combustion chamber?