Potential Group Purchase - Wiseco GS650 741cc pistons

[Tooheys]

Yes I'm all good to go sorry my notifications for this thread don't seem to be working

 

[Tooheys]

There's another gs650g parts bike in here at the local vintage Japanese salvage shop if anyone is struggling to find a 650 top end on ebay. I may go buy that 1 if they give me my usual preferred pricing on the not-as-fast-selling parts.

Chuck,

i would be be interested in this top end depending on price. Finding it really hard to find top ends in Aus. I can get funds to you and only require shipping to Aspen CO

 

[Chuck78]

Chuck,

i would be be interested in this top end depending on price. Finding it really hard to find top ends in Aus. I can get funds to you and only require shipping to Aspen CO

PM sent...

 

[Chuck78]

Update

Update

Yes I'm all good to go sorry my notifications for this thread don't seem to be working

*Ace07 (2 sets)
*Chuck78 (possibly 2 sets)
*Tkent02
*Frankenwabbit
*Old Colt
*Tooheys
Boontonmike
charnotx
nerobro(?)
roeme (not ready yet)
Rob.M (?)
drey6 (my local friend, not ready yet)

Okay so we have 9 to 12 interested buyers now, 6 of which have stated they are ready to buy now (need at least 1 more to get the preferred pricing unless Ace or myself double up and get 2 sets).

Any more confirmations on people ready to go?
Boontonmike
charnotx
nerobro(?)
Rob.M (?)
drey6 (???) (EDIT: Not yet, Still waiting on insurance check from lady totalling his 86 ninja last fall)

 

[charnotx]

Any progress? Definitely still interested, and ready.

 

[Ace07]

Hey Guys,

I just got off the phone with Wiseco. Since I am ordering 40 pistons they are going to cost me $78.94 including shipping and tax. I am guessing that I should be able to get a set of pistons in a flat rate box from the post office, so I am thinking it would cost me a additional $15 dollars to get them sent to each person. Now I have been doing some digging around to find a good interest rate on a loan, and I have found a decent one, but it does add cost to the pistons.

Currently Wisco is doing some final research to ensure they have all the information they need to make the pistons. Once they tell me everything is ready to go, I will let everyone know, and I will give everyone 1 week after that to pay me for the pistons in advance. Paying for the pistons in advance will guarantee you would only pay the $78.94 per piston plus $15-$20 dollars in shipping. Once that week is up I will take a loan out to cover the rest of the payments, and whenever I do that the price will increase. It will not be much, just to cover the loan cost and a small service charge. Don't worry I am not going to increase the price alot, because I still want you guys to be able to afford them. I just want to give a little extra incentive on paying in advance.

 

[Chuck78]

If this is delayed until the end of June, there is a good chance I could purchase the remaining sets myself for those who have not paid, maybe even a few extra. Pending my house sale.

 

[Chuck78]

As I had hoped, the local vintage Japanese bike salvage yard and parts shop actually had a GS 1100 G head gasket in stock. This is an MLs gasket, and I needed to compare it to an oem gs750 77-79 gasket in order to determine cam chain tunnel o-ring delete gasket dimensions for our 650-740cc gaskets.

Currently things are a bit hectic around here time-wise, but I will try to get an hour of free time in to do some gasket comparisons and contact gasketstogo.com. I need to finish moving my shop stuff from the house that's being sold, including my GS650 head and cylinders, which will be needed so that I can take measurements on the MLS gasket replacing the corner oil passage oversized head stud holes, as well as cam chain tunnel dimensions 750 obsolete gasket vs GS1100G MLS gasket. I do have an OEM 650 gasket. It has dome type of coating on it. I am not sure if it is MLS or not, did not pull it off the shelf when I last spotted it.

 

[charnotx]

Been having trouble sourcing a 650 top end for the swap. Anyone have a source at a reasonable price and condition for this project?

 

[Chuck78]

I just sent Tooheys info on where there is a 650 top end. Ask him if he's getting that one.

If still looking, call up David Mayo & son at Rockdale Cycles in Georgia & ask if they have any GS650's, had buncha gs's when I was there sept. buying a Rickman CR900 racer frame and 14 GS1100E swingarms...

 

[charnotx]

Will do, that's for the heads up

 

[Chuck78]

Head gaskets

Head gaskets

I emailed Athena about MLS 65mm gaskets, their GS head gaskets actually seem pretty nice. 750 uses corner oil seals still, sealed 550 gasket set did not include them but stud hole oil passage corner openings are not sized smaller however. Missing the seals?

GS1100G MLS gasket used to convert 850/1000 superceded composite gaskets to MLS deletes cam chain tunnel oil seal ring and corner stud combination oil pressure passage seals and undersizes corner holes & tunnel opening to replace seal with MLS gasket material. The Wiseco apparently did the same thing. Much smaller tunnel openings in gasket.

 

[Chuck78]

Not sure I will have time to retrieve the OEM 650 gasket before I leave for the weekend but I will attempt to submit info for 5-7 MLS gaskets from gasketstogo.com with this info.

They all measured .051-.053" or 1.3-1.4mm uncompressed MLS. I did not unwrap the Wiseco NOS composite gasket

 

[Nessism]

That Athena gasket is not MLS. It's a regular composite gasket with a silver outer skin layer.

 

[Chuck78]

Good to know Ed, thank you.

Quote info sent to gasketstogo.com. John Baker, the owner, immediately emailed me back and said he would work on an approximate quote and get pricing back to me over the weekend, & said we can discuss any additional details / concerns / issues after that.

Like I said, the community for early VW diesels (primarily rabbit pickups and lesser the rabbit cars) uses gasketstogo.com with great success. This should be no different here.

 

[Old Colt]

That Athena gasket is not MLS. It's a regular composite gasket with a silver outer skin layer.

Thank you for stating that these are not MLS gaskets.
FWIW 1.3mm might be a bit thick for our needs. We really need to get a piston in an engine to check the setup height. Then the gasket thickness can be determined. Granted 95% of the setups will not really matter just what the squish area turns out to be but it would be nice to have it right.

 

[Chuck78]

I can get an OEM 650 gasket shipped off to Thailand asap & wait until after we have all received our pistons to order the MLS I suppose. We can have Mike sell the 25 year old Wiseco NOS gaskets to those who don't care enough to wait for a piston-in-hole deck height measurement. I generally always mill a skim coat off of the deck and the head to ensure trueness and an excellent mating surface, so 1.3mm may not be bad. The compressed thickness will be slightly less, fwiw.

Old Colt, I was hoping you would chime in a good bit on head gasket technical specifications, thank you. Please voice any other concerns or suggestions you have.

I could also send dimensions to Cometic for a composite quote, but I think they are around $80 each for a small batch if I recall correctly from forum posts from here a few years ago.

 

[Old Colt]

It would be nice to get a clay imprint between the head and piston just to see what the chamber looks like at TDC and what the true squish is.
At an estimate of $80 for Cometic the Gaskets to go might be very competitive, might be damn nice gaskets too and for me much less work than making an O-ringed copper gasket.

I am thinking I should get my azz in gear and assemble the bottom end of this motor. I am thinking I am glad I never contoured the chambers to fit the OEM 750 pistons.

 

[Chuck78]

Here ya go!

Hi Chuck,

Cost to make your gasket as a 1.3 or 1.4mm MLS head gasket would be as follows:

1-4 pcs: $119.95/ea.
5+ pcs: $79.95/ea.

Lead time is 3-4 weeks at the moment.

We can work from a scale scan you make (more info: www.gasketstogo.com/scans)

Or you can send your pattern to me (www.gasketstogo.com/mailing)

If you decide to order I would send you a PayPal invoice you can pay by credit card once we are ready to proceed.

I will attach an info sheet for MLS gaskets to this message.

Regards,

John



--
Regards,

John M. Baker
Owner
www.gasketstogo.com

I recall the gs750/850-920cc I built a few years ago having the piston about .016" in the hole @ TDC after a very light skimming of the block deck surface to mill it smooth. I was told that the GS1100G MLS gasket I was using had a compressed thickness of .040", and that would put me at an ideal quench height to help ward off any detonation (pre-ignition/"pinging").

In my hot rod/musclecar days with my GTO fanatic dad, I had learned in that community that in a water cooled small block chevy v8, .039"-.045" quench height was preferred to keep you clear of detonation concerns. Could be that these air cooled engines that run much hotter (270 degrees vs 210 water cooled) need more quench/squish band height due to different operating parameters? Heat of compression and latent heat combined is what causes detonation (like how a diesel operates intentionally).

I will research this more.

 

[Old Colt]

The engines I build which are considerably smaller than that old big iron are run considerably tighter clearance. Common practice is around 0.030 clearance. Most of my engines are in the 0.015 to .020 range.
With this piston setup the clearance up in the chamber needs to be checked as well as the outer squish area.
Those prices are good. Obviously there are other costs involved such as shipping in and out.