Ooooh, looks like it'll be piston rings then... - Page 2

Dukedesmo · 27-09-2018, 08:18 AM

Don't want to put a downer on anyone's business but I have an ongoing bore wear problem with my Monster.

The short of it is I had the cylinders bored & plated to 944cc by Langcourt, who I had previously used to replate my 916 cylinders which have been fine; plenty of compression and uses no oil between services.

Afterwards it always used a lot of oil and within a year/3,000 miles the bores were worn so much that they needed plating again. I sent them back to Langcourt who re-did them at a discounted price and everything was re-assembled meticulously but oil usage continued despite engine running well and having plenty of compression.

Over the last few years the oil usage has increased and now it is very smoky, using way too much oil and I know it is bore wear causing the problem. Compression, whilst still good is also reduced and so I'm going to get them plated again over the winter.

Now I don't know exactly what the cause is but the engine was assembled both times with new rings (new pistons 1st time), correctly gapped and run with quality oil so unless there's a ring material compatibility problem? (I did look into this as there was some doubt on JE rings being OK with Nikasil? and so fitted a different brand the second time) I can only assume the bores are not hard-wearing enough?

I am not the only person to have had this problem, I know of two others that had the same issue at around the same time.

As I said at the top of this post, I don't want to damage anyone's business reputation and I have had cylinders plated by Langcourt that are still going strong 10 yrs down the line and so I've held back from saying too much about the problems but I also want to tell it like it is because I'm facing a 3rd replate in 12,000 miles which to blunt is a pain in the arse.

I'm now looking to get mine redone by Poeton of Gloucester of whom I have heard good things.

Darren69 · 27-09-2018, 08:51 AM

Excuse my ignorance but are they Nikasil new from the factory?

Kato · 27-09-2018, 12:40 PM

Quote:

Originally Posted by darren69

excuse my ignorance but are they nikasil new from the factory?

yes........

Dukedesmo · 27-09-2018, 01:05 PM

Yes AFAIK Nikasil is the OEM finish but there are varying reports of chrome not interacting with nikasil very well and many piston rings are chrome, OEM rings maybe cast iron?

I understand there are also various types of nikasil with differing compositions which may add to the mix?

As I said I can't be 100% sure the plating wasn't right but something definitely wasn't and I really want to get it right 3rd time around.

I would welcome anyone's knowledge on the matter...

Kato · 27-09-2018, 01:27 PM

A brief history nickel silicon-carbide plating......Grabbed from the WWW

The 'Nikasil' surface treatment process was developed in the late '60s by Mahle, the German
piston manufacturer, in conjunction with NSU and Daimler-Benz (468) originally to provide a
wear resistant coating for Al-alloy rotor casings fitted to ****el rotary engines. It was the
result of a long programme of material combinations tried by many ****el licencees to
overcome a 'ripple' wear pattern characteristic of this engine type.

The process used electrolytic deposition to plate the Al-alloy casings with nickel in which
particles of silicon-carbide smaller than 1 micron (0.001mm) were dispersed. After finishing
treatment the plating was only 200 microns (0.2mm) thick in the ****el application (870).
Porsche first used 'Nikasil' coating in a normal piston engine for (air-cooled) Al-alloy
cylinders in the 1971 5L development of the F12 Type 912 unit and, compared with the
previous Cr-plated Al-alloy cylinders ('Chromal') found it increased power (302). The layer
may have been thinner than that used in the ****el engine (a 'few hundredths of a
millimetre' was quoted in (241) when applied in 1973 to the Porsche Type 911/83
competition engine (also air-cooled).

The reported improvement in oil consumption of the DFV with 'Nikasil'-treated Al-alloy
cylinders may have been a consequence of more rapid and complete bedding-in of the piston
rings, which is what is thought to have occurred in the Porsche 912 engine. If this then
reduced combustion gas blow-by a power gain would have been observed.

Kato · 27-09-2018, 02:12 PM

In something like 40 plus engines I have never had an issue with plated bores that wasn't caused by me....and usually because I tried to do something like hone a cylinder (something that should never be done or needed after the final finish at the factory), very interested to to learn and understand your problem DD, not sure where you got the info re differing types of Nikasil certainly not something I'd ever heard, I have run with chrome and cast rings all OK, my observation is I usually get the best results from very tight tolerances, having said that I'm talking very minor improvements.

I used to get all my plating done in Germany, however the company I used recommended Langcourt when I complained they were to slow and have been using them now for nearly 15 years without issue, I also know Langcourt do all of williams and cosworth's plating so they know a thing or two about it.

Now not saying they haven't screwed up on your's !!

Macflurry · 16-10-2018, 09:02 PM

Sorry I've not updated this for a while but I was waiting for a positive update!!

And here it is, the bike lives!!

Took the barrels off and the vertical piston had a shattered oil ring which also explains the metal shards when I drained the oil.

Took both barrels, pistons and heads to Louigi Moto to get inspected and I can't say a big enough thank you to Richard!! I only called in for a quick visual inspection and an idea of how much it would cost to fix. Before I knew it Richard had stopped what he was working on, checked my kit and was away foraging through his parts bins to help me get the bike on the road without forking out a small fortune. An hour later and he had found me a replacement piston, honed my bores and got me an oil ring to fit for a voluntary contribution to his brew fund!!

I got back home, started putting everything back together and then shattered the oil ring on my horizontal cylinder!!

Luckily I found a guy on eBay Germany that just sells the oil rings for £40 so I didn't have to buy the whole set!!

Got the new ring, fitted everything together and when I fired it up it was spitting out more smoke than before and physically spitting oil out of the back of the exhaust and the joints... Bugger!!

At this point the only thing I could think was that I had either damaged or badly fitted the valve seals and luckily I had a spare set of them. Swapped out the vertical ones and seemed to be slightly better then swapped out the horizontal ones and BOOM!! Oil and smoke free!! When I looked at the exhaust seal there were two small nicks in the rubber. I must have snagged it while fitting the shims back on.

I noticed that the plugs were getting black pretty quickly while testing it. Took it out for a spin yesterday and it started misfiring after about 10-15 minutes. When it was smoking the only way it would run was with the fuel screw out 4.5 turns so today I dialled them back and took it out again. So far, so good!! I was out for an hour today and it needs a little refining but it's running great!!

27-09-2018, 08:18 AM	#16
Dukedesmo Registered User Join Date: Sep 2010 Location: Leics Bike: M900 Posts: 2,838	Don't want to put a downer on anyone's business but I have an ongoing bore wear problem with my Monster. The short of it is I had the cylinders bored & plated to 944cc by Langcourt, who I had previously used to replate my 916 cylinders which have been fine; plenty of compression and uses no oil between services. Afterwards it always used a lot of oil and within a year/3,000 miles the bores were worn so much that they needed plating again. I sent them back to Langcourt who re-did them at a discounted price and everything was re-assembled meticulously but oil usage continued despite engine running well and having plenty of compression. Over the last few years the oil usage has increased and now it is very smoky, using way too much oil and I know it is bore wear causing the problem. Compression, whilst still good is also reduced and so I'm going to get them plated again over the winter. Now I don't know exactly what the cause is but the engine was assembled both times with new rings (new pistons 1st time), correctly gapped and run with quality oil so unless there's a ring material compatibility problem? (I did look into this as there was some doubt on JE rings being OK with Nikasil? and so fitted a different brand the second time) I can only assume the bores are not hard-wearing enough? I am not the only person to have had this problem, I know of two others that had the same issue at around the same time. As I said at the top of this post, I don't want to damage anyone's business reputation and I have had cylinders plated by Langcourt that are still going strong 10 yrs down the line and so I've held back from saying too much about the problems but I also want to tell it like it is because I'm facing a 3rd replate in 12,000 miles which to blunt is a pain in the arse. I'm now looking to get mine redone by Poeton of Gloucester of whom I have heard good things. __________________ M900, 916, LeMans II.

27-09-2018, 08:51 AM	#17
Darren69 Transmaniacon MOC Join Date: Sep 2013 Location: Sutton In Ashfield Bike: Multiple Monsters Posts: 6,022	Excuse my ignorance but are they Nikasil new from the factory? __________________ Roast Beef Monster! Termignoni and Bucci - Italian for pipe and slippers! S4 Fogarty, S4R 07T, 748, Series 1 Mirage

27-09-2018, 01:05 PM	#19
Dukedesmo Registered User Join Date: Sep 2010 Location: Leics Bike: M900 Posts: 2,838	Yes AFAIK Nikasil is the OEM finish but there are varying reports of chrome not interacting with nikasil very well and many piston rings are chrome, OEM rings maybe cast iron? I understand there are also various types of nikasil with differing compositions which may add to the mix? As I said I can't be 100% sure the plating wasn't right but something definitely wasn't and I really want to get it right 3rd time around. I would welcome anyone's knowledge on the matter... __________________ M900, 916, LeMans II.

27-09-2018, 01:27 PM	#20
Kato Dismantled Join Date: Feb 2006 Location: East Molesey Bike: Multiple Monsters Posts: 2,222	A brief history nickel silicon-carbide plating......Grabbed from the WWW The 'Nikasil' surface treatment process was developed in the late '60s by Mahle, the German piston manufacturer, in conjunction with NSU and Daimler-Benz (468) originally to provide a wear resistant coating for Al-alloy rotor casings fitted to **el rotary engines. It was the result of a long programme of material combinations tried by many el licencees to overcome a 'ripple' wear pattern characteristic of this engine type. The process used electrolytic deposition to plate the Al-alloy casings with nickel in which particles of silicon-carbide smaller than 1 micron (0.001mm) were dispersed. After finishing treatment the plating was only 200 microns (0.2mm) thick in the el application (870). Porsche first used 'Nikasil' coating in a normal piston engine for (air-cooled) Al-alloy cylinders in the 1971 5L development of the F12 Type 912 unit and, compared with the previous Cr-plated Al-alloy cylinders ('Chromal') found it increased power (302). The layer may have been thinner than that used in the **el engine (a 'few hundredths of a millimetre' was quoted in (241) when applied in 1973 to the Porsche Type 911/83 competition engine (also air-cooled). The reported improvement in oil consumption of the DFV with 'Nikasil'-treated Al-alloy cylinders may have been a consequence of more rapid and complete bedding-in of the piston rings, which is what is thought to have occurred in the Porsche 912 engine. If this then reduced combustion gas blow-by a power gain would have been observed. __________________ "Political correctness is just intellectual colonialism and psychological fascism for the creation of thought crime"

27-09-2018, 02:12 PM	#21
Kato Dismantled Join Date: Feb 2006 Location: East Molesey Bike: Multiple Monsters Posts: 2,222	In something like 40 plus engines I have never had an issue with plated bores that wasn't caused by me....and usually because I tried to do something like hone a cylinder (something that should never be done or needed after the final finish at the factory), very interested to to learn and understand your problem DD, not sure where you got the info re differing types of Nikasil certainly not something I'd ever heard, I have run with chrome and cast rings all OK, my observation is I usually get the best results from very tight tolerances, having said that I'm talking very minor improvements. I used to get all my plating done in Germany, however the company I used recommended Langcourt when I complained they were to slow and have been using them now for nearly 15 years without issue, I also know Langcourt do all of williams and cosworth's plating so they know a thing or two about it. Now not saying they haven't screwed up on your's !! __________________ "Political correctness is just intellectual colonialism and psychological fascism for the creation of thought crime"

16-10-2018, 09:02 PM	#22
Macflurry Registered User Join Date: Mar 2018 Location: Blakeney Bike: M900 Posts: 134	Sorry I've not updated this for a while but I was waiting for a positive update!! And here it is, the bike lives!! Took the barrels off and the vertical piston had a shattered oil ring which also explains the metal shards when I drained the oil. Took both barrels, pistons and heads to Louigi Moto to get inspected and I can't say a big enough thank you to Richard!! I only called in for a quick visual inspection and an idea of how much it would cost to fix. Before I knew it Richard had stopped what he was working on, checked my kit and was away foraging through his parts bins to help me get the bike on the road without forking out a small fortune. An hour later and he had found me a replacement piston, honed my bores and got me an oil ring to fit for a voluntary contribution to his brew fund!! I got back home, started putting everything back together and then shattered the oil ring on my horizontal cylinder!! Luckily I found a guy on eBay Germany that just sells the oil rings for £40 so I didn't have to buy the whole set!! Got the new ring, fitted everything together and when I fired it up it was spitting out more smoke than before and physically spitting oil out of the back of the exhaust and the joints... Bugger!! At this point the only thing I could think was that I had either damaged or badly fitted the valve seals and luckily I had a spare set of them. Swapped out the vertical ones and seemed to be slightly better then swapped out the horizontal ones and BOOM!! Oil and smoke free!! When I looked at the exhaust seal there were two small nicks in the rubber. I must have snagged it while fitting the shims back on. I noticed that the plugs were getting black pretty quickly while testing it. Took it out for a spin yesterday and it started misfiring after about 10-15 minutes. When it was smoking the only way it would run was with the fuel screw out 4.5 turns so today I dialled them back and took it out again. So far, so good!! I was out for an hour today and it needs a little refining but it's running great!!