Wiseco Piston Pics and Comments

[blsnelling]

Brad, What type of breakin did you
do with this piston kit.
I wouldn't have thought all the machining
lines would be worn off this early.



Lee

I started and warmed it up several times with a cool down between. Only after the 3rd or 4th time did I rev it enough to put a tach on it. I then put it in the wood as seen in the Ash videos. I'd make a cut and then let it idle for a few seconds between cuts. It wasn't extensive, but perhaps a little more than I normally would. I've never seen one wear this much though. However, the piston is perfectly smooth with no smearing or scoring at all. I'll probably have it back off shortly and get some pics of it.

 

[indiansprings]

Good video Brad, saw sounds good. That hard oak is the world we live in.
I chalk up the great performance to those sexy holes in the air filter cover!lol
I know you got it that way, couldn't help but notice those. It'll be interesting to see how it looks after some serious useage. I don't think the sideplay is an issue as long as the needles aren't exposed, if they were it would be a different issue. Glad it worked.

 

[Paul001]

I'm still interested in knowing the context of the quote you provided. Who's lead engineer brought up the issue? Wiseco or Baileys? It's wonderful they are now figuring out that spec's were not followed, would be interesting to know how the first run got past Q/C.

Sounds like a lot of Bill Clinton speak with regards to these issues.

Hopefully they get it sorted out and Baileys is able to manage the customer relations side of things.

 

[blsnelling]

The filter was quite clean after nearly a full tank, perhaps cleaner than normal. These do like to cake up but work well in spite of it.

I'm going to put a degree wheel on it tonight. I did not alter port timing the first time round. I only widened and shaped the ports. Depending on what I find, I may or may not do some more port work. If nothing else, I want to see the piston, and check up on the bearing deal. Hopefully the new bearing will show up before I'm ready to go back together.

 

[blsnelling]

I'm still interested in knowing the context of the quote you provided. Who's lead engineer brought up the issue? Wiseco or Baileys? It's wonderful they are now figuring out that spec's were not followed, would be interesting to know how the first run got past Q/C.

Sounds like a lot of Bill Clinton speak with regards to these issues.

Hopefully they get it sorted out and Baileys is able to manage the customer relations side of things.

I think it was Wisecos engineer that brought up the bearing issue. I'm not 100% sure on that though. Gregg would have to answer that.

 

[indiansprings]

If it keeps the filter cleaner, it may be the mod of the future. You'll have three hundred people experimenting with what size holes and angle of the holes work best.lol I've run the 660 with the filter cover off and it doesn't seem to be as dirty, just depends what your doing.

What rpms were running no load? I think I've got mine too fat.

 

[blsnelling]

What rpms were running no load? I think I've got mine too fat.

As you saw, I was playing around with it quite a bit. I was seeing from 13,500-14,200. It seemed to be getting faster as I went, requiring me to keep richening it up. It'll probably continue to do that as the saw breaks in. I believe spec on a stock 066 is 13,000.

 

[kevlar]

looks good Brad! So what's she feel like- possible a little torquier from the heavier piston, didn't seem any slower to spool up.

 

[blsnelling]

looks good Brad! So what's she feel like- possible a little torquier from the heavier piston, didn't seem any slower to spool up.

RPMs aren't what I hoped for in a ported saw. I don't know if the weight of the piston is playing a factory or not. That's why I'm going to put a degree wheel on it.

 

[leeha]

I started and warmed it up several times with a cool down between. Only after the 3rd or 4th time did I rev it enough to put a tach on it. I then put it in the wood as seen in the Ash videos. I'd make a cut and then let it idle for a few seconds between cuts. It wasn't extensive, but perhaps a little more than I normally would. I've never seen one wear this much though. However, the piston is perfectly smooth with no smearing or scoring at all. I'll probably have it back off shortly and get some pics of it.

Sounds like you broke it in ok. I think i would have done a couple light cuts then let it completely cool and repeat a couple times. According to Wiseco it is important to do a few heat cycles so the piston will take shape to the cylinder.
Your .0015 - .002 piston clearance might be a bit tight for a forged piston. Wiseco and myself decided to with
.003 - .0035 on the 166 pistons we did. But the 166 is also a 56mm bore. I'm sure the 066 must be a bit smaller.


Lee

 

[blsnelling]

According to Wiseco it is important to do a few heat cycles so the piston will take shape to the cylinder.

Which indicates to me that they're expecting more break-in wear than we're used to.

Your .0015 - .002 piston clearance might be a bit tight for a forged piston. Wiseco and myself decided to with
.003 - .0035 on the 166 pistons we did. But the 166 is also a 56mm bore. I'm sure the 066 must be a bit smaller.

That was at the very bottom of the skirt. It was significantly smaller than that at the crown.

 

[mtngun]

I'm going to put a degree wheel on it tonight. I did not alter port timing the first time round. I only widened and shaped the ports.

This dataholic would enjoy seeing yet another set of 066/660 port timing data.

Thanks as always for your detailed reports, Brad.

Paul001, I don't want to publicly embarrass our sponser, and I don't know what goes on behind the scenes in spec'ing these products -- but I can guess, having done some design and outsourcing in one of my previous careers.

Manufacturing is a new thing for Bailey's. They recently hired a QC guy, but I doubt if they have a technical designer per se. They are probably relying heavily on their vendor's design expertise. Until recently it appears they mostly cloned OEM specs and didn't get too creative except for enlarging cylinder bores.

One can imagine the discussion going on now between Bailey's and Wiseco, with each pointing a finger at the other. It happens all the time when you are working with vendors and contractors.

I've said it before, and I'll say it again, the Bailey's products are gradually getting better, and I appreciate them giving us more choices. This forged piston idea was a big step for them, maybe a little too big. I am still optimistic that things are getting better, and the bottom line is that thanks to Baileys, we have many choices now that we didn't have before.

 

[Grande Dog]

Howdy,
In this particular case we supplied Wiseco with the OEM samples. Right now, it sounds like they had the specs right (45 degrees off center line) for the pins but, the indexing jig must have been off the center line of the piston. So the pins did end up being 90 degrees apart, just not on center. I'm still waiting on the disposition.
Regards
Gregg

 

[Paul001]

This dataholic would enjoy seeing yet another set of 066/660 port timing data.

Thanks as always for your detailed reports, Brad.

Paul001, I don't want to publicly embarrass our sponser, and I don't know what goes on behind the scenes in spec'ing these products -- but I can guess, having done some design and outsourcing in one of my previous careers.

Manufacturing is a new thing for Bailey's. They recently hired a QC guy, but I doubt if they have a technical designer per se. They are probably relying heavily on their vendor's design expertise. Until recently it appears they mostly cloned OEM specs and didn't get too creative except for enlarging cylinder bores.

One can imagine the discussion going on now between Bailey's and Wiseco, with each pointing a finger at the other. It happens all the time when you are working with vendors and contractors.

I've said it before, and I'll say it again, the Bailey's products are gradually getting better, and I appreciate them giving us more choices. This forged piston idea was a big step for them, maybe a little too big. I am still optimistic that things are getting better, and the bottom line is that thanks to Baileys, we have many choices now that we didn't have before.

Having spent a portion of my life in a similar position as you, I agree. Hence, part of the reasoning behind my loaded question.

I have no doubt that Baileys will handle the customer service issue better most anyone would. I'd like to see this project succeed if for no other reason than the ability to provide my customers (and me personally) with another reasonably priced option, besides OEM.

 

[Bowtie]

Howdy,
In this particular case we supplied Wiseco with the OEM samples. Right now, it sounds like they had the specs right (45 degrees off center line) for the pins but, the indexing jig must have been off the center line of the piston. So the pins did end up being 90 degrees apart, just not on center. I'm still waiting on the disposition.
Regards
Gregg

Thats odd of Wiseco to make an error like that. I ran their pistons in outlaw mini sprints in Colorado in the 90's and they were they racing piston producer to beat. I have also seen their products in other applications and for them to screw up like that puts them on par with Toyota's current SNAFU on a smaller scale.

That being said, I know they will fix it. Someone in QC needs walking papers.

 

[matt9923]

Thats odd of Wiseco to make an error like that. I ran their pistons in outlaw mini sprints in Colorado in the 90's and they were they racing piston producer to beat. I have also seen their products in other applications and for them to screw up like that puts them on par with Toyota's current SNAFU on a smaller scale.

That being said, I know they will fix it. Someone in QC needs walking papers.

Iv had quite a few bikes with them. Usually good quality.

 

[blsnelling]

Here are pics of the 066 Wiseco piston after 1 tank of fuel, as shown in the vids yesterday. As mentioned before, I warmed up the saw 4 times with complete cool downs before revving it enough to put a tach on it. I then started bucking about 20" logs with a few seconds of idle between to cool down.

This piston isn't hurt, but it appears to me that it's a little tight for the bore. Additional careful break-in will be in order.

The cylinder looks just like it did when I put it together. BTW, all ports were beveled and then the edges sanded by hand. I then check for snags with a ring.

I always get polishing immediately on the bottom of the intake skirt, but never anywhere near this much.

You can see wear near the crown about all the way around the piston.

Please ignore the little divot. That was a boo boo

 

[mtngun]

Please ignore the little divot. That was a boo boo

Glad I'm not the only one who makes boo-boos.

Thanks again for the detailed report.

You mentioned something about checking port timing ?

 

[blsnelling]

Port timings are:

Exhaust 96°
Transfers 116°
Intake 81°

Very little port timing was changed during the initial porting. The intake may have been dropped 1°, that's it.

 

[timberwolf]

That rubbing all the way around the crown is a sure sign of too tight a piston fit or too much heat. It was right on the edge of failure.

That rub up top tell that the piston crown grew due to thermal expansion from its cold measurment to the full diamiter of the bore. At little math and the average crown temperature can be worked out, assuming the rubbing occured before the bore reached full temperature and had no chance to expand adding to piston clearance (which was likely the case).