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I apologize for the absence. @worntorn , I can still discuss but would like to say much of the concern was answered by the empirical evidence of the guys here that have actually used nikasil lined bores. John brings up great points about the market versus the negative responses feedback in a forum. There are several American V twin forums littered with armchair engineers lacking information, experience, and the ability to learn past their bias. For 14 years they have been bashing our billet, nikasil lined bores. While the thousands of cylinders we ve made are on the bikes of people out enjoying their bikes. Meanwhile, the factory continues to court Nikasil because they know. I ve had to cynically chuckle at some of the logic behind the naysayers. In this thread and/or one of the articles linked here, I ve seen a quorum that Nikasil is great for racing or powersports. Pick a motorsport and iconic racer of the last thirty years, excepting for rules of sanctioning bodies, you will be hard pressed to find non-nikasil lined bores. Obviously, this statement isn t an absolute. As an example; dryblock, alcohol, supercharged hayabusa dragbikes making 800 hp. I m aware of a few others and certain there are some I don t know. Far and away the overwhelming majority will be nikasil plated. However, in the same breath they will claim it doesn t work for a non racing, normal daily driver. Huh? I have to question the rudimentary mechanical understanding behind these type of statements. Here is something to consider. My passion is pre world war one motorcycles. In 2017, the AMCA contacted me to do an interview about Nikasil being used to rejuvenate previously non servicable cylinders. The reason is my friend had us nikasil his ultra rare 1912 Henderson cylinders. He used this bike to compete in the Cannonball. 3100 miles without a top end failure on a cylinder that was dug out of the ground and displayed in shop for 30 years. In the last four years I have met nearly all of the Cannonballers that compete with teen and older bikes. The reason is the nikasil lined bore doesn t fail and it is one less thing to worry about repairing/maintaining or carrying spares during the race. What does this have to do with the viability of plated bores? Cannonball bikes are the antithesis of todays performance racing powerplants. They are air cooled, total loss oiling, atmospheric intake, I over E, 5:1 static compression ratio, .008" clearance tractor engines that can rev all the way up 2500 rpm. Nikasil plated cylinders ARE the choice of Cannonballers. They are a far cry from the performance, stress, mechanical forces experienced in any of the Nortons in question. The argument that nikasil is for high performance engines only is wrong. Sorry for the ramble.

















j
 
Rodney Heaton said:
I apologize for the absence. @worntorn , I can still discuss but would like to say much of the concern was answered by the empirical evidence of the guys here that have actually used nikasil lined bores. John brings up great points about the market versus the negative responses feedback in a forum. There are several American V twin forums littered with armchair engineers lacking information, experience, and the ability to learn past their bias. For 14 years they have been bashing our billet, nikasil lined bores. While the thousands of cylinders we ve made are on the bikes of people out enjoying their bikes. Meanwhile, the factory continues to court Nikasil because they know. I ve had to cynically chuckle at some of the logic behind the naysayers. In this thread and/or one of the articles linked here, I ve seen a quorum that Nikasil is great for racing or powersports. Pick a motorsport and iconic racer of the last thirty years, excepting for rules of sanctioning bodies, you will be hard pressed to find non-nikasil lined bores. Obviously, this statement isn t an absolute. As an example; dryblock, alcohol, supercharged hayabusa dragbikes making 800 hp. I m aware of a few others and certain there are some I don t know. Far and away the overwhelming majority will be nikasil plated. However, in the same breath they will claim it doesn t work for a non racing, normal daily driver. Huh? I have to question the rudimentary mechanical understanding behind these type of statements. Here is something to consider. My passion is pre world war one motorcycles. In 2017, the AMCA contacted me to do an interview about Nikasil being used to rejuvenate previously non servicable cylinders. The reason is my friend had us nikasil his ultra rare 1912 Henderson cylinders. He used this bike to compete in the Cannonball. 3100 miles without a top end failure on a cylinder that was dug out of the ground and displayed in shop for 30 years. In the last four years I have met nearly all of the Cannonballers that compete with teen and older bikes. The reason is the nikasil lined bore doesn t fail and it is one less thing to worry about repairing/maintaining or carrying spares during the race. What does this have to do with the viability of plated bores? Cannonball bikes are the antithesis of todays performance racing powerplants. They are air cooled, total loss oiling, atmospheric intake, I over E, 5:1 static compression ratio, .008" clearance tractor engines that can rev all the way up 2500 rpm. Nikasil plated cylinders ARE the choice of Cannonballers. They are a far cry from the performance, stress, mechanical forces experienced in any of the Nortons in question. The argument that nikasil is for high performance engines only is wrong. Sorry for the ramble.

















j
Click to expand...


That was my first thought with some of the arguments against roadbike use of Nikasil.
If it withstands the rigors of racing why would it somehow not be up to roadbike use?


Glen
 
John and Rodney, please don't take the negative stuff too seriously. As you said, you get that sort of response a lot on forums. I'd hate to see either one of you stop providing updates and technical info just because of some negative vibes from a few posters. If you look at this thread, you will notice that there are way more positive responders than negative. It's just that the negative ones tend to post more to support their position. The positive ones are usually happy to post once or twice to say how much they appreciate your efforts, and then go on to something else. And to be fair to the posters with the "negative" replies, they don't seem to be trolls trying to wind people up. They are raising what seems to them to be serious questions. The problem is, once you take a position, there's a real tendency to keep trying to "win" the discussion, as opposed to looking for truth.

Not meaning to be critical of anyone in particular, just trying to encourage those with good information to share.

Ken
 
lcrken said:
John and Rodney, please don't take the negative stuff too seriously. As you said, you get that sort of response a lot on forums. I'd hate to see either one of you stop providing updates and technical info just because of some negative vibes from a few posters. If you look at this thread, you will notice that there are way more positive responders than negative. It's just that the negative ones tend to post more to support their position. The positive ones are usually happy to post once or twice to say how much they appreciate your efforts, and then go on to something else. And to be fair to the posters with the "negative" replies, they don't seem to be trolls trying to wind people up. They are raising what seems to them to be serious questions. The problem is, once you take a position, there's a real tendency to keep trying to "win" the discussion, as opposed to looking for truth.

Not meaning to be critical of anyone in particular, just trying to encourage those with good information to share.

Ken
Click to expand...
Personally, I think we should be grateful that new improved parts are still being developed for the 51 year old Commando.
 
lcrken said:
John and Rodney, please don't take the negative stuff too seriously. As you said, you get that sort of response a lot on forums. I'd hate to see either one of you stop providing updates and technical info just because of some negative vibes from a few posters. If you look at this thread, you will notice that there are way more positive responders than negative. It's just that the negative ones tend to post more to support their position. The positive ones are usually happy to post once or twice to say how much they appreciate your efforts, and then go on to something else. And to be fair to the posters with the "negative" replies, they don't seem to be trolls trying to wind people up. They are raising what seems to them to be serious questions. The problem is, once you take a position, there's a real tendency to keep trying to "win" the discussion, as opposed to looking for truth.

Not meaning to be critical of anyone in particular, just trying to encourage those with good information to share.

Ken
Click to expand...

Ken

Excellent post, my thoughts exactly. I put this offering up on the site to get everyone's feedback. When needed, I believe I must, politely, address the negative issues. Not to slam the author, or his or her data, but to objectively argue the merits of our experience. Nothing worse than to launch a new product which is already doomed by potential neagative customer feedback.
 
Rodney Heaton said:
I apologize for the absence. @worntorn , I can still discuss but would like to say much of the concern was answered by the empirical evidence of the guys here that have actually used nikasil lined bores. John brings up great points about the market versus the negative responses feedback in a forum. There are several American V twin forums littered with armchair engineers lacking information, experience, and the ability to learn past their bias. For 14 years they have been bashing our billet, nikasil lined bores. While the thousands of cylinders we ve made are on the bikes of people out enjoying their bikes. Meanwhile, the factory continues to court Nikasil because they know. I ve had to cynically chuckle at some of the logic behind the naysayers. In this thread and/or one of the articles linked here, I ve seen a quorum that Nikasil is great for racing or powersports. Pick a motorsport and iconic racer of the last thirty years, excepting for rules of sanctioning bodies, you will be hard pressed to find non-nikasil lined bores. Obviously, this statement isn t an absolute. As an example; dryblock, alcohol, supercharged hayabusa dragbikes making 800 hp. I m aware of a few others and certain there are some I don t know. Far and away the overwhelming majority will be nikasil plated. However, in the same breath they will claim it doesn t work for a non racing, normal daily driver. Huh? I have to question the rudimentary mechanical understanding behind these type of statements. Here is something to consider. My passion is pre world war one motorcycles. In 2017, the AMCA contacted me to do an interview about Nikasil being used to rejuvenate previously non servicable cylinders. The reason is my friend had us nikasil his ultra rare 1912 Henderson cylinders. He used this bike to compete in the Cannonball. 3100 miles without a top end failure on a cylinder that was dug out of the ground and displayed in shop for 30 years. In the last four years I have met nearly all of the Cannonballers that compete with teen and older bikes. The reason is the nikasil lined bore doesn t fail and it is one less thing to worry about repairing/maintaining or carrying spares during the race. What does this have to do with the viability of plated bores? Cannonball bikes are the antithesis of todays performance racing powerplants. They are air cooled, total loss oiling, atmospheric intake, I over E, 5:1 static compression ratio, .008" clearance tractor engines that can rev all the way up 2500 rpm. Nikasil plated cylinders ARE the choice of Cannonballers. They are a far cry from the performance, stress, mechanical forces experienced in any of the Nortons in question. The argument that nikasil is for high performance engines only is wrong. Sorry for the ramble. j
Click to expand...

Thanks Rodney

I appreciate your input

To all Access members, please note that Rodney just joined our forum. He did this at my request to share his expertise with Nikasil plating. I believe that if we are going to discuss the issue, it is best to have an "expert" in the field with years of experience at one of the premier companies that does the process

Thanks again Rodney for taking time to be part of this discussion.

And let me add, I do a lot more learning on this site than teaching

John
 
lcrken said:
And to be fair to the posters with the "negative" replies, they don't seem to be trolls trying to wind people up. They are raising what seems to them to be serious questions.

Not meaning to be critical of anyone in particular, just trying to encourage those with good information to share.

Ken
Click to expand...

I completely agree with this. It is for this reason I have been hesitant to go into detail about some of the articles posted. I believe diligent persons have sought information and raised what they believe are concerns relating to billet, plated cylinders. I'm happy to share any information I have. If I can do it in a way that doesn't discredit the time or understanding of another but can instead help them to have a better more accurate understanding. I'm in a fortunate and enviable position of seeing firsthand this type of, "What if we made it. . . " in a scale much larger than just a single marquee. I try to keep that in perspective when involved in this type of scenario. I sometimes forget, I see and am privy to things that most people have to dig very hard to get a few kernels of knowledge. To be fair you wouldn't want me to do your taxes, represent you in a court of law or, build your house. lol
 
I have a question about pistons for the subject billet/Nikasil cylinders, but before posing the question want to provide a brief piece of peripherally related background information.

Background
For several decades the Japanese 2- and 4-stroke motocross engines (and I assume others – KTM, Husqvarna?) employed Nikasil-coated aluminum cylinders. The presently available 4-stroke liquid-cooled engines employing ultra-short slipper skirt pistons have a recommended piston change interval on the order of 15-20 hr. Although this sounds like a very short use life, consider that 20 hr of use would entail 40 x 30 minute motos, where a rider is unmercifully and non-stop thrashing the living hell out of the engine for 30+ minutes/moto. With high compression and therefore minimal piston to valve clearance the short piston change interval is intended to avoid piston to valve interference resulting from piston skirt wear that allows slight rocking of the piston that can lead to piston/valve clearance issues. However, the situation is easily remedied by simply slipping a new piston and rings into the existing bore and being back in the game with the original piston fit restored. There is no sizing or honing of anything - simply replacing piston and rings and reassembling.

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It is my understanding that the fit of such pistons is very near 0.001” clearance and that the factories control bore size, straightness and piston dimensions extremely well (0.0001-0.0002”).

So back to my question regarding pistons for a billet aluminum Nikasil Norton cylinder. In light of the foregoing, I assume a piston will be available for the subject cylinder, since no fitting will be taking place? I’m also curious, any thoughts at this point in time on what the piston alloy and fit might be for the new cylinder? Would the pistons be cast, forged, billet? Would the piston be as long as possible or might it be a somewhat shorter style piston?

Perhaps it is premature to be posing these questions and if so I apologize for getting the cart ahead of the horse. Thank you in advance for your thoughts and insight on this subject.
 
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I can give you some answer to your last question, but it might leave more questions unanswered.
On water cooled Yamaha TZ 350 the alloy bores are nickasil coated, the pistons should be changed every 300 racing miles, the one piston ring every GP. The piston comes in three sizes on the skirt, to maintain that .003 tho clearance between the two.
Each engine is different, I have to try running in each new piston/ring on a TZ by keeping off the 12 000 max rev limit and just for 3 laps, and run at 25: 1 petrol/ oil ratio. I only suffered 1 engine siezure when I failed to do it.
 
WZ507 said:
I have a question about pistons for the subject billet/Nikasil cylinders, but before posing the question want to provide a brief piece of peripherally related background information.

Background
For several decades the Japanese 2- and 4-stroke motocross engines (and I assume others – KTM, Husqvarna?) employed Nikasil-coated aluminum cylinders. The presently available 4-stroke liquid-cooled engines employing ultra-short slipper skirt pistons have a recommended piston change interval on the order of 15-20 hr. Although this sounds like a very short use life, consider that 20 hr of use would entail 40 x 30 minute motos, where a rider is unmercifully and non-stop thrashing the living hell out of the engine for 30+ minutes/moto. With high compression and therefore minimal piston to valve clearance the short piston change interval is intended to avoid piston to valve interference resulting from piston skirt wear that allows slight rocking of the piston that can lead to piston/valve clearance issues. However, the situation is easily remedied by simply slipping a new piston and rings into the existing bore and being back in the game with the original piston fit restored. There is no sizing or honing of anything - simply replacing piston and rings and reassembling.

View attachment 15837 View attachment 15838

It is my understanding that the fit of such pistons is very near 0.001” clearance and that the factories control bore size, straightness and piston dimensions extremely well (0.0001-0.0002”).

So back to my question regarding pistons for a billet aluminum Nikasil Norton cylinder. In light of the foregoing, I assume a piston will be available for the subject cylinder, since no fitting will be taking place? I’m also curious, any thoughts at this point in time on what the piston alloy and fit might be for the new cylinder? Would the pistons be cast, forged, billet? Would the piston be as long as possible or might it be a somewhat shorter style piston?

Perhaps it is premature to be posing these questions and if so I apologize for getting the cart ahead of the horse. Thank you in advance for your thoughts and insight on this subject.
Click to expand...

Precise fitting of pistons to Nikasil bores is going to be an issue. I don't think you'll get the Taiwanese piston people to custom make their pistons for tighter clearance.

4032 alloy pistons would have lower expansion than the 2618 alloy for those who are obsessed with clearance. Both alloys are available but if you want them to fit a stock bore of exactly 77mm then you'll have to order custom pistons dimensioned for an exact tight clearance and the clearance for 2618 alloy will have to be different than the clearance for 4032 alloy.

Custom sizes are available. I specify a different clearance for my 4032 pistons than I do for the 2618 alloy (preferred in racing). For the Nikasil alum cylinders John would either have to bore each cylinder to fit the pistons provided by the customer or provide pistons with his cylinders. Clearances for the Nikasil alum cylinders will be around .0035" for 2618 pistons. This has already been tested with some of my pistons in Europe. The graphite coating allows an even tighter clearance.

The 4032 alloy pistons on the street should tolerate down to .0025" clearance and even tighter with the graphite coating. .001" installation clearance is allowable with the graphite coating but that will increase to a minimum running clearance after break in. See 4032 alloy piston with graphite coating and .001" installation clearance below. Weight of this 73.5mm bare piston is only 177 grams. The dot allows you to accurately measure the piston at the bare metal instead of just measuring at the coating.

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I think the best option will be to make the cylinders with an exact bore of 77mm and then get custom diameter pistons to fit with a tighter clearance - that way you can get replacement pistons. Its a hassle but when you're coming out with a new product with new improvements then you have to complete the picture with a comprehensive combination that actually takes advantage of the improvement of Nikasil alum cylinders.
 
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WZ507 said:
I have a question about pistons for the subject billet/Nikasil cylinders, but before posing the question want to provide a brief piece of peripherally related background information.

Background
For several decades the Japanese 2- and 4-stroke motocross engines (and I assume others – KTM, Husqvarna?) employed Nikasil-coated aluminum cylinders. The presently available 4-stroke liquid-cooled engines employing ultra-short slipper skirt pistons have a recommended piston change interval on the order of 15-20 hr. Although this sounds like a very short use life, consider that 20 hr of use would entail 40 x 30 minute motos, where a rider is unmercifully and non-stop thrashing the living hell out of the engine for 30+ minutes/moto. With high compression and therefore minimal piston to valve clearance the short piston change interval is intended to avoid piston to valve interference resulting from piston skirt wear that allows slight rocking of the piston that can lead to piston/valve clearance issues. However, the situation is easily remedied by simply slipping a new piston and rings into the existing bore and being back in the game with the original piston fit restored. There is no sizing or honing of anything - simply replacing piston and rings and reassembling.

View attachment 15837 View attachment 15838

It is my understanding that the fit of such pistons is very near 0.001” clearance and that the factories control bore size, straightness and piston dimensions extremely well (0.0001-0.0002”).

So back to my question regarding pistons for a billet aluminum Nikasil Norton cylinder. In light of the foregoing, I assume a piston will be available for the subject cylinder, since no fitting will be taking place? I’m also curious, any thoughts at this point in time on what the piston alloy and fit might be for the new cylinder? Would the pistons be cast, forged, billet? Would the piston be as long as possible or might it be a somewhat shorter style piston?

Perhaps it is premature to be posing these questions and if so I apologize for getting the cart ahead of the horse. Thank you in advance for your thoughts and insight on this subject.
Click to expand...
Great questions with good information. Just want to be clear the pistons running clearances near .001" are Most commonly, 4 stroke, all aluminum, liquid cooled MODERN motorbikes. There are only a few exceptions where an aircooled (motorcycle) engine will run that tight of a piston to wall clearance.
 
jseng1 said:
I think the best option will be to make the cylinders with an exact bore of 77mm and then get custom diameter pistons to fit with a tighter clearance - that way you can get replacement pistons. Its a hassle but when you're coming out with a new product with new improvements then you have to complete the picture with a comprehensive combination that actually takes advantage of the improvement of Nikasil alum cylinders.
Click to expand...
Yes! This is what all the OE's do. Make the bore a standard MM size. The onus is always on the builder to confirm accurate clearance. We always recommend our customers to send the pistons along with the blocks for accurate clearances.
 
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