Freestyle First PHP 898 with Nikasil!

[Matt_E]

$325 minus the cost to have a non Nikasil cylinder honed or bored when it's time to rebuild ( if Nikasil is very slow to wear).

I might be mistaken, but if it needs to be re-coated, then the old coating must be removed first. Is that included in the $325?
Zach, you mention that your CR500 engines with nic'd sleeves run cooler. I was always under the impression that the reason Nikasil heat transfer works so well is because it doesn't have to deal with a sleeve to begin with. So are you improving heat transfer of a steel sleeve by putting a layer of Nikasil on it?

Thanks for the info.

 

[egbrig]

Matt, the shorter heat path along with less heat do to the lower friction all add up to a cooler running cylinder. While the steel sleeve is still a factor in the heat path, the lower coeficient of friction between the ring/piston and cylinder make for less heat build up and therefore less heat to disapate, so still better than just steel. Also there is a up to a 4% increase in power due to the lower friction.

 

[Cannibal]

I might be mistaken, but if it needs to be re-coated, then the old coating must be removed first. Is that included in the $325?
Zach, you mention that your CR500 engines with nic'd sleeves run cooler. I was always under the impression that the reason Nikasil heat transfer works so well is because it doesn't have to deal with a sleeve to begin with. So are you improving heat transfer of a steel sleeve by putting a layer of Nikasil on it?

Thanks for the info.

I think he's saying when it's time for a rebuild, you may not need to bore and hone because of the Nikasil. So Nikasil it once and rebuild it many times, giving a potential cost savings each time. But yes, when it's time to recoat, it's time to bore and hone then recoat from what I know about Nikasil (automotive application).

I'm curious if them running cooler is just an effect of lower friction?

 

[egbrig]

You wont need to rebore the steel sleeve if the wear or damage is minimal because the nikasil coating is honed to the final diameter.

 

[Freakrider]

I think he's saying when it's time for a rebuild, you may not need to bore and hone because of the Nikasil. So Nikasil it once and rebuild it many times, giving a potential cost savings each time. But yes, when it's time to recoat, it's time to bore and hone then recoat from what I know about Nikasil (automotive application).

I'm curious if them running cooler is just an effect of lower friction?

That's what I was thinking that the cost in the long run is offset by not having to bore or hone in the future.

 

[powerhouseperformance]

I might be mistaken, but if it needs to be re-coated, then the old coating must be removed first. Is that included in the $325?
Zach, you mention that your CR500 engines with nic'd sleeves run cooler. I was always under the impression that the reason Nikasil heat transfer works so well is because it doesn't have to deal with a sleeve to begin with. So are you improving heat transfer of a steel sleeve by putting a layer of Nikasil on it?

Thanks for the info.

No it doesn't improve the heat transfer coefficient of the sleeve. The cooler is achieved from the lower friction. If you've ever seen a 2 stroker get run on the dyno you will see when it hits the beginning part of the power band to the time it ends the pull things get real hot real fast. Now imagine that same engine making two of those dyno runs every lap for 30 laps...that Nic makes a pretty big impact on water temp. Less friction into heat=more power to rip that prop before you leave your setup wake

 

[Billybo455]

No it doesn't improve the heat transfer coefficient of the sleeve. The cooler is achieved from the lower friction. If you've ever seen a 2 stroker get run on the dyno you will see when it hits the beginning part of the power band to the time it ends the pull things get real hot real fast. Now imagine that same engine making two of those dyno runs every lap for 30 laps...that Nic makes a pretty big impact on water temp. Less friction into heat=more power to rip that prop before you leave your setup wake

they used cylinders with sleeves that were plated in nikasil for that dyno run? plated sleeves is something new for me. just trying to see both sides of the story. pretty sure most of these ski motors aren't even close to the operating temp they should be.

 

[motobehrens]

Plating steel sleeves is something the vintage MX guys do to preserve their cylinders. I looked into having a 61X cylinder plated not too long ago. It was a used ported sleeved big bore on it's last bore that I was looking at, and thought Nikasil would be a good cost effective Idea for keeping it at it's last bore, or even plating down to it's second to last bore. The price to plate a twin cylinder was approx 450$. At the time, it didn't make $$ sense. I was told they(Powerseal) can plate to a thickness of .020"

 

[powerhouseperformance]

they used cylinders with sleeves that were plated in nikasil for that dyno run? plated sleeves is something new for me. just trying to see both sides of the story. pretty sure most of these ski motors aren't even close to the operating temp they should be.

Blake you missed the point I was making. Just because a jetski engine has an unlimited supply of cooling water doesn't mean that the engine isn't dumping some piston/cylinder frictional heat energy right out the pisser. It just means its never going to overheat like the cr500 dirt tracker might. I brought the dyno run example up because most guys have not witnessed how fast heat is built up in a loaded engine...when you watch it, it's surprising. Most of the time you are just trying to keep whatever your riding wot pointed in a safe direction vs. observing heat build up. The fact that we can actually observe cooler run temps on a dirt tracker with a fixed amount of cooling supply is enough to see that there was a loss of internal heat friction. Not to mention the engine is flat out faster

 

[Nuklear6]

I use powerseal for all my micro sprint engines nikasil. They do a fantastic job and do it for me for $135 per cylinder (including removing old coating). Nikasil is in my opinion the superior cylinder wall material. And for years ive shook my head as to why yamaha didnt design the 701+ cylinder to not use sleeves and use a nik cylinder wall. I mean come on CR250s have been nik since 86'. The main reason to use nik in a jetski is, being with a wet exhaust the steel cylinder walls are very prone to rust and corrosion. Normally one exhaust port is always left open when stopped or stored which make any water and moisture in the exhaust port start to rust the cylinder walls. That all being said i agree with the above heat/ friction reduction with nik but honestly do not feel in a freestyle jet ski application that reduction would matter enough as most engines are not run wide open long enough for those reductions to make a noticeable performance improvement. PHP please do not take this as a dig or at all negative. I too am a nikasil guy just dont feel its worth it in this application.

 

[Tommygunz]

I did the Nikasil on my cylinder enhance the longevity of it and to have it stay at 898. Any performance gain is a bonus......

 

[motobehrens]

I did the Nikasil on my cylinder enhance the longevity of it and to have it stay at 898. Any performance gain is a bonus......

This idea definitely has merit, and I would have done the same to a 61x/62t if the prices weren't based off of a cylinder they(powerseal) had never plated before and required new fixtures etc be made. The only problem being that a catastrophic failure could mean a resleeve and a replate. A proper Nikasil on Aluminum cylinder would just be repaired/welded and replated, which could make it more affordable to maintain your bore size long term. I forget the cost of resleeve and replate vs. repair/weld Al and replate. Maybe one of the cylinder manufacturers should offer two options, one with steel sleeves and one with Nikasil on aluminum.

 

[egbrig]

One thing that shows how effective the nikasil's lower friction is, when you turn over a steel sleeved engine it takes a bit of force and the bigger the bore the more force (more ring surface area) . On a nikasil'd cylinder it almost rolls on its own. The more gas pressure you have pressing the rings into the cylinder wall (higher rpm) the more power it takes to turn the engine.

 

[swannysxr]

Correct me if I am wrong, my understanding is that you would need to run plasma moly rings to benefit from the nikasil coating?

 

[egbrig]

In two strokes you don't need plasma moly rings because we re-ring much sooner than a four stroke ever would. A chrome faced ring works well with nikasil in two strokes minimal oil enviroment.

 

[KTM434]

I don't run engines that cost me $6000 to build but I do run billet stroker motors and big bore motors with port work. I am not on the last bore on any of my engines so I haven't really had to worry about it but I've always considered nikisil plating my jetski engines when I get to my last bore for longevity reasons. Once you need to resleeve your engine and port new sleeves and bore the new sleeves you would have saved money by just plating your cylinder. When I raced harescrambles I had 4 racing seasons on my CR250 that I bought used... Was doing my seasonal top end rebuild and noticed the nikisil was wearing off. Sent it out to be replated (cost me like $100-120 at the time) then I just ran the original bore size and threw new pistons/rings in there. I also bought a brand new CR125 that I bored 3mm over and had ported and plated after only a few hours of riding it just for a baseline comparison (nikisil is not that expensive when you consider a B-pipe is $700, TNT chamber is $500, PFP is $1400 and almost everyone runs them). The plating doesn't last forever (I was told it's only .003" thick) but it lasts much longer than a steel bore and depending how long you want to keep an engine or a specific bore size. I think it's a great option for jetski engines as well. I don't see it as a performance aspect for freestyle/freeride with the lower/inconsistent engine loads and lower heat buildup but a jetski racer could definitely benefit from the less friction/added power and needing to keep the engine size within class regulations. Although I don't race and I'm not on my last bore I do think the nikisil is a great way to prevent rust and scoring from water ingestion and an engine that sits for any amount of time without fogging or coating the cylinders while there is water in the exhaust. Tpain when you said it was expensive I figured you'd say a higher number. $325 is not bad when you're building a $20,000 ski!

Oh! Another nice thing about nikisil is knowing that your bore size will be consistent and you can keep brand new pistons and gaskets on a shelf to plan ahead for routine rebuilds. That saves down time when you already know your cylinder bore is within spec and you know what size pistons you need before even taking the motor out and tearing down for inspection.

 

[Tommygunz]

Very true! I guess $325 is a drop in the bucket when I look at my build costing me $25 grand +...... But its a worthwhile investment and hopefully will get my motor put together in the next few days depending on work.

 

[feartheride]

i tried to google powerseal nickasi, no hits, whos got a link

 

[KTM434]

You spelled it wrong. I believe my cylinder was sent out to Wisconsin to get replated when I had it done.

 

[motobehrens]

Millenium is based out of Wisconsin, and is who Eric Gorr(dirt bikes) uses for his engines

USChrome is based out of Wisconsin

Powerseal is based out of Pennsylvania, and is who the local AZ vintage MX guys were using for their plating.



Nikasil is a trademarked term, so you may not find that exact name on either companies site. Each has a variation of "Nickel Silicon Carbide" plating. i.e. NiCom, NikaSeal,