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Discussion Starter · #1 ·
on the recent big bore thread the nik a sil coating for the cylinder liners was mentioned as (it seemed) an optional coating for the big bore liners. A brief search indicated that the nik a sil is a coating applied to aluminum bores. Is it also applied to steel of iron cylinder liners? Are the factory liners coated?
 

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the stock bores are nikasil plated.

The wiseco 904 kit uses conventional iron liners.

http://en.wikipedia.org/wiki/Nikasil

It's praised for it's longevity, but some feel it's benefits are overstated by the manufacturers because it saves them money on production. There has been some engine failures due to nikasil. It is a bit controversial.

Most on this board think it's the greatest because of it's longevity. I chose the wiseco kit because of the ability to rebore/overbore. Nikasil requires special tools to hone/bore and most shops do not have the proper equipment.

[ This message was edited by: sweatmachine on 2007-02-06 14:48 ]
 

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Yes they are. You can buy a BB kit from BC already sil'd, but it's pricey, SCCTRIM is running a BC kit.

***** you fast Sweat!

Greg

[ This message was edited by: bonnieblackinfl on 2007-02-06 14:49 ]
 

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Sweat, hadn't heard about probs with Nikasil bores. As for longevity, my son's `93 R1100RS has close to 120k miles on her on stock pistons and still has good compression. They are a bear to break in though...
 

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Not much to add here than what has already been said. I'm unaware of issue's with nikasil coated barrel's in motors. The main reason I chose this over the wiseco was longevity, and I'm kinda anal about doing everything I can for the best possible end result.

You'll find a thread in the cafe section of the forum where Thrux-Ton-Up is rebuilding his bike...( definately one of the nicest thruxton's anywhere )...you can check that thread for the specific post stating mileage on his motor when he tore it down. I believe he said the center of the bores only showed .0001 wear.

You can also notice that in the photo's of machines bb thread that you can still clearly see the honing marks in the bores after some 17K miles..( is that # correct machine? )..I believe in the cafe section thread theres a statement that the nikasil plated barrel's should or could go 150K miles.

This doesnt mean that the wiseco's are junk....just different. Wiseco's stuff is based/tested upon on racing applications, in that enviroment motor's are being torn down regularly.

Apple's / oranges...

Nikasil is good stuff, but it's costly. Most time's ya get what ya pay for, not always...but most times.
 

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Here's what Bill Gately of Bonneville Performance had to say re: British Customs 904cc kit (that is nikasiled)

If I am reading the website correctly they bore the factory cylinder and you get what's left--2mm. see below. That is a pretty shi!*y deal--the reason we went with the iron alloy sleeves when we were developing the WISECO kit was because we were too thin to go with the factory set when we went to 92mm. We then had a choice between using an aluminum sleeve or an iron alloy sleeve--we took the route of most competition racing teams and went with iron for durability and the ability to hone to freshen the engine with a new set of rings or even bore for oversized pistons.
and here's what he said about the Wiseco kit:

I got about 22K out mine before I took it apart for my stroker engine rebuild. It had enough wear to warrant a set of rings and honing the cylinders. Other than that everything was good. Now having said that you must know that I thoroughly thrashed this engine everytime I rode it--this included 1200 mile rides through Death Valley running it up on the pipe steering it with the throttle--and had it on the dyno so many times testing things that I am very pleased that it stayed together.
When asked how long a normal-use motor would last:

I would say you would easily see 40 -50K as long as you don't thrash your engine --if you do expect less. Personally I would freshen my cylinders every 30k just because it is the smart thing to do and the cost is minimal to keep your engine running strong.
Sorry for all the cutting and pasting, but links to the Delphi forum never seem to work...
 

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I suppose thats true...consider the source of purchase ;)

I will say that it is a nice kit however. The barrel's bores are matched to the pistons, and while I wasnt very impressed with the color of the barrel..( see the above anal comment )..I've got no complaint's about the kit to this point.


You can cry foul about pricing for aftermarket component's for our bike's...and in alot of cases the tears are justifiable. It's a niche market for the Triumphs, perhap's it would be different if there were as many aftermarket choice's for us as there are for other manufacturer's bikes.


1 thing I did gain out of my rig with the BC kit...( I still have my stock barrel ) :)
 

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On 2007-02-06 16:18, SCCTrim wrote:
I will say that it is a nice kit however. The barrel's bores are matched to the pistons...
See, I don't know what they mean by that. ANY bores are matched to pistons. My wiseco pistons wouldn't even come close to fitting in the bores out of the box, the machinist has to fit them, as with any rebore.
 

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I didnt see your post thats just ahead of mine, when I posted I was responding to the post prior.

I think we need our own forum...lol


I admire Bill, the work he is doing with the race team, and the pride he takes in his equipment and his products. Bill is a great guy to deal with, and I would certainly buy from him again. While I have not had a negative experience with dealing with BC, I do not feel the same way about them.


Considering thing's I've read on other forums, I wouldnt expect Bill to have anything positive to say about BC or anyone from that organization. There appear's to be some history there, I dont know anything about it and wont pretend to.


I didnt mean to insinuate that you somehow bought or wiseco produce's a inferior product. I only meant that I'm anal about stuff and thought that the BC kit would be a better end result regarding longevity.

As for the comment about only having 2mm left for the 904 kit, my motor appears to be fine. I feel if there were a issue I could contact sean at BC and hopefully come to a resolution that would agree with us both.

The 1200 kit in development will be using sleeves that are 2.7mm thick btw...for what it's worth. Again this kit was developed and based upon a racing application, it only makes sense that they would want iron liners for durability. And they are tearing motor's down and rebuilding them on a semi-regular basis.

All together a different scenario when compared to a street bike. The other hting about iron liners is I would assume they wouldnt disapate heat like aluminum...( read assume )...which for me anyway is another nod for what I bought.


After 22k miles Bill's motor had enough wear to warrant new ring's and a hone job. Granted Bill use's his stuff, it's hard to tell how many dyno run's that bike went thru in that 22k miles...but after 17K on your motor the bores look great.


It's good that we as owner's have option's regarding mods...even if they are limited when compared to other brands.
 

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I didnt mean to insinuate that you somehow bought or wiseco produce's a inferior product. I only meant that I'm anal about stuff and thought that the BC kit would be a better end result regarding longevity.
My feelings aren't hurt ol' buddy!



The 1200 kit in development will be using sleeves that are 2.7mm thick btw...for what it's worth. Again this kit was developed and based upon a racing application, it only makes sense that they would want iron liners for durability. And they are tearing motor's down and rebuilding them on a semi-regular basis.
Mmmmm, 1200 kit. MMMM.

Yeah, I figure by the time my motor needs a 'refresh' it'll expand a little bit, if you know what I mean... :wink:
 

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Some cars used nikasil, the early Jaguar V8 engines I think, and had problems with it, but mostly because the oil was not changed often and it got acidic which I hear will erase the nikasil coating off the bores.

I hear nikasil is easy to damage, and when damaged means a new cylinder.

Iron wears out, and must have wider tolerances between the bore and piston, but is forgiving and can be honed and bored out.

Brett
 

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Discussion Starter · #14 ·
thanks for all of the info.

I have a 904 Wiseco kit that I was measuring up today, to assess the amount of material that needs to come out of the sleeves. I think that I'll just stay with the iron sleeve as planned, to many potential downsides to the nik a sil to play with it for a street ride.
 

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I don't think nikasil is really a "downside", I think it's like expensive insurance, there is extreme longivity with it. After 50-70,000 miles w/the wiesco kit and it's time to refresh; do you believe you will be able to leave well enough alone and not upgrade to a larger displacement kit that will be on the market by then?

I wouldn't be able too, the bug keeps you looking for "more power". I'm almost never satisfied.

Greg
:-D
 

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Agreed Greg, on all points. I'm already absolutely drooling over the thought of having 20 more horse's for the bonnie.

Truthfully I probably just need to leave it alone...( and build a 1200cc speedmaster )... :)
 

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Porsche and BMW had some problems as well as Jag with Nik-a-sil in the early 90's. I can't remember specifics - but had to do with low grade fuel / fuel additives that affected the coating. The fuels have since corrected what ever the issue was and there is no affect on the coatings now. Many bikes - guzzi's, Honda, Triumph use Nik-a-sil. It is not really a cost savings as its not easy to accomplish. Would be cheaper/easier to use iron blocks/liners and not have to go through the plating process. But alloy motors and their weight savings seem to be the norm so Nik-a-sil is an excellent low friction coating that just so happens to last a very long time. Back in my automotive days it was said 2 identical motors except for the blocks - one iron - the other alloy would produce different results - the iron block actually making more consistant power than the alloy block. But then you have to factor in the weight savings - with 7 pounds being equal to roughly 1 HP in tradeoff. The alloy block would still come out ahead.

John
 

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Back when I first heard of Nikasil (on '80's vintage BMW Airheads, I think) the stated advantages were enhanced heat transfer and lighter weight. If memory serves, it is an aluminum hardening process that chemically bonds some kind of nickel/silicon compound to the walls of the cylinder. Though conventional thinkers didn't favor it at first (due to an inability to overbore) it was soon a sought-after feature as the cylinders just didn't wear. From what I understand, overbores are not necessary at rebuild time...just rings and a valve job.
 
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