105mm Piston - Group buy?

thanks goose !

for the ring details ill just find the wiseco ringset number, we want 1 comp ring and one oil scraper

the skirt on that prox i mentioned is stupid narrow a wider one is what we want (same as oem or the jbs one) but the rod clearance etc is good

regarding the coating on top i dont think its necessary because in this engine there is a very quick build up of carbon over the crown which IMHO does about the same thing

the skirt coatings also not necessary but is worth doing

can you please confirm with him at some stage that we can get as an option in the same run of 12 the same piston without the top machined ? (for spanner and his ducati head)

I would be happy to get one with no machining at all to the top + 1mm on the
height would be good.

Might wont two like that.

Agree the skirt needs to be large and strong.

Will confirm this week regarding the Spanner special. I'm going to draft a written spec proposal of the custom pistons for Wiseco's consideration. I want to be sure we are all on the same page before plunking down our hard earned cash.

Initially, I will send it to Bushy and Spanner (check you inbox's) for confirmation that I have the correct specs and special request for the Spanner specials for what we want. Then off to Wiseco. I have a huge project due Wednesday so it may have to wait until Thursday. Check your inbox's Thursday and, upon approval/correction from you guys, I'll forward to our contact at Wiseco. Sound good?

Yes sound good thanks goose I'll post the ringset number today

ringset number is 4103F

it contains 2 compression rings and one oil ring

just be clear we only want one compression ring groove in the piston

I'll send you and spanner a pm of the proposed email to Wiseco by the end of this week. Gotta run to work right now.

we have another hands up for a piston or 2 if needed to make it happen

so in total its at 10 solid plus 3 extras if needed

im ready, lets go.

:thumbright::thumbright::thumbright:

Sorry guys, I have been dropping the ball. Work went completely sideways and focus hasn't been at a premium. Got the ball back in my hands now. Let's do this. Working up email right now.

Hi guys, Spanner and Bushy, check your inboxes. Once we vet the email. Ill send it!

105mm piston-Group buy

Hey! Is intressrad to be in this piston purchase. Is it too late for expressions of interest?

Not too late at all. I'm sending the specs (big fat thanks to Bushy and Spanner for their insights and expertise) on Monday. After we pin down what they can and can't do, and finalize the price, i'll post up for final commitments and how to pay. Then we are rolling. I'm anticipating placing the order and delivering payment by the end of this week. I'll keep the board posted. Yep, this thing in ON!!

I can't take it anymore.. I really miss my bike.

I'd like one piston please.

I think I read above that no case machining is neccesary.

That's the goal. No machining, just sleeves and piston to fit OEM rod for the 628 crank.

Augh ... I want one just to be able to build one in the future, but don't have the cash. When is full payment due? At the start I assume, or?

tourist said:

Augh ... I want one just to be able to build one in the future, but don't have the cash. When is full payment due? At the start I assume, or?

Click to expand...

Stay tuned, I may be buying an extra or 2 subject to the reply from Wiseco.

Email sent yesterday:

Deal Al,

Thanks for speaking to me a couple of weeks ago about the custom pistons for my group’s Husaberg 650 project. I’ve discussed the types of pistons we believe would best suit our needs and, of course, would appreciate your insights as well. Below are the specifications we would like to see with regard to our order. As it stands right now, we wish to order 12 custom pistons [pending the price, I may be able to order more]. Please send me some estimates of the price per piston without any coatings and with the skirt coating.

So, here are the specs:

We’d like to have a piston final sized to run in an Iron liner with a finished diameter of 4.125" = 104.775.

The engines are liquid cooled about 690cc (after oversized piston and sleeve) with compression ratio up to 12.5 to one and 70-75 rwhp.

If we use just over a thou per inch of bore diameter the clearance can be 4.2-4.4 thou giving a piston diameter of 104.665mm. Thus, in practical terms 104.67mm but we would like your opinion on the clearance.

Also, we wish to have increased depth and diameter valve pockets over stock to cover wider range of valves than the jbs piston (see STP file attached). [file attached]

Distance from the pin center to piston top to 24.5mm. This puts the squish equal to the head gasket thickness (1.2mm)

Piston total volume, minus 13.9cc.

For rod clearance see attached pdf drawing of the “628" rod.

Further regarding rod clearance the underside of the piston can be the same as the 100mm Prox piston in your stock, ie.:

PN# 01.6606.A

A: Diameter: 99.95mm

B: Total height: 41.20mm

C: Pin size: 20.00mm

D: Compression height: 14.50mm

G:Boss Space: 23.00mm

However, we believe the skirt on the Prox piston is too narrow and would like a wider stronger skirt like the oem Wossner and Elko/Mahle Husaberg pistons or the jbs “105mm”.

The Ringset can be your 4127GF but used on the piston with one compression and one oil Ringset only.

See attached STP file of the top of the piston for valve pockets, volume and squish band. [file attached]

Here is a link to the discussion amongst the group. “Bushmechanic” and "Spanner" are by far the most knowledgeable on the topic and I'll likely consult both of them with any questions. While I'd like to pretend to understand all this, I'm at best a hamfisted shade-tree wrench that is grateful to others much more knowledgeable than myself.

http://husaberg.org/mechanical/21450-105mm-piston-group-buy-2.html

Spanner has asked if it is possible for us to ask for some of the pistons (one or 2) machined but without the top being done. Is that a possibility?

We also would like to know the estimated minimum weight of the pistons and if they can be made lighter than about 320gm (piston only). Additionally, do you have a taper bore20mm piston pin available? For example, the Wossner 20mm pin is taper bore at 66gm and the Mahle at 70gm, a solid pin is about 80gm.

Please let me know asap if the 104.665 mm piston is doable as we are also arranging an increased capacity “sleeve” order.

Thank you for your time and consideration. If you have any questions, feel free to contact me at [email protected] I’ll do my best to answer, however, I’ll likely have to consult briefly with others who are much more knowledgeable than I am regarding specs.

Thank you!

[all my contact info]

Quick update: Just got off phone with Wiseco. Specs received and Al's on it! He's a good guy.

As an aside, he's strenuously urging skirt coating and armor top coating due to compression and the results from their in-house testing. Still, we agreed to hold that discussion until the remainder of the project is vetted. Stay tuned!

If you help me find 08 Fe650, then I would take three. I just started looking for one. Need help finding one. I want 2008.

Did he say How much do the skirt and top coatings add to the price ?

Mine cracked underneath at about 350 hrs on the bridge running from the pin to the skirt

Top coating would not help that area (rev limit would lol)

The skirt coating will be all gone at about 100 hrs IMHO but I agree it's a good thing

ask Al his thoughts on preventing this one

Stupid question. Will these fit in the 644 motor or just the 628's?