Page 1 of 3 1 2 3 LastLast
Results 1 to 10 of 21
  1. #1
    cubex's Avatar
    Join Date
    May 2011
    Location
    Atlanta Ga
    Posts
    31

    nikisil vs steel sleeves

    was wondering what the advantages or disadvantages were replacing nikisil cylinders with sleeved cylinders?


  2. #2
    20 feet Boy's Avatar
    Join Date
    Jul 2010
    Location
    Bend OR
    Posts
    1,257
    +1
    1
    You can bored a steal sleeved 4 to 6 times Theres more life on the cylinder. A nikisil cylinder will have to be fixed or replace. Having it bored cost cheaper . It just cost more up front to have the sleeves put it. I am not a fan of chroma nikisil from the 80. But the newer kind seems to work.

  3. #3

    Join Date
    Jan 2006
    Location
    Texas City, Texas
    Posts
    1,249
    +1
    15
    Better heat transfer from the cylinders to the cooling water with the nicasil coating.

    The drag coefficient is less...... it is slicker. It is so slick and hard that it takes an unusually long time for the rings to seat. Ten hours on the water seems to be the average when people report that their compression has increased.

    Because they are so hard, they seam to resist mild lean seizures much better than steel sleeved cylinders.

  4. #4
    shhr's Avatar
    Join Date
    May 2005
    Location
    Springfield,TN
    Posts
    2,546
    +1
    311
    Better heat transfer from the cylinders to the cooling water with the nicasil coating.

    The drag coefficient is less...... it is slicker. It is so slick and hard that it takes an unusually long time for the rings to seat. Ten hours on the water seems to be the average when people report that their compression has increased.

    Because they are so hard, they seam to resist mild lean seizures much better than steel sleeved cylinders.
    +1

  5. #5
    Moderator RX951's Avatar
    Join Date
    Apr 2005
    Location
    League City, Texas
    Posts
    16,066
    +1
    23
    Quote Originally Posted by salty View Post
    Better heat transfer from the cylinders to the cooling water with the nicasil coating.

    The drag coefficient is less...... it is slicker. It is so slick and hard that it takes an unusually long time for the rings to seat. Ten hours on the water seems to be the average when people report that their compression has increased.

    Because they are so hard, they seam to resist mild lean seizures much better than steel sleeved cylinders.

    +1 ^

    Nicasil is much better. One of the big performance advantages of nikasil-type bore over traditional cast iron sleeves (other than a major weight saving) is the ability to operate an engine with smaller piston to bore clearances since the piston and the cylinder will tend to expand a similar amount when heated. For that reason, it will be important for builders to accurately measure the bores after machining, then select the proper size pistons which will give him a clearance which satisfies the engine manufacturers specifications. .e.g. Yamaha.... Close attention should also be paid to the ring-end gap to ensure compliance with manufacturers specs.

    I've had pistons get "squeaked" pers se, run lean, and all that is needed is a little muratic acid was in the bore to remove the aluminum deposit and stick a new piston in and you are good to go. What gives Nickasil its excellent low-wear properties is the presence of silicon carbide which is much harder than steel.

    This Nicasil technology is not new, but proven and sucessful...30+ years. YAmaha did right applying nicasil on cylidner bores. Porsche also have used Nicasil. They use a different coating now called Alusil, but same concept....benefits of Nikasil in a nutshell are wear resistance, lower friction and oil control.

  6. #6
    cubex's Avatar
    Join Date
    May 2011
    Location
    Atlanta Ga
    Posts
    31
    Thanks for the replys,looks like ill have the cylinder replated.

  7. #7
    So can nikasil handle a hone with new pistons and rings or does it need to be replated ( assuming that the. Walls are not nicked) ?

  8. #8
    PolarisNut's Avatar
    Join Date
    Dec 2006
    Location
    Lower Michigan
    Posts
    1,809
    Quote Originally Posted by MossBack View Post
    So can nikasil handle a hone with new pistons and rings or does it need to be replated ( assuming that the. Walls are not nicked) ?
    Yes, nikasil should be able to be honed several times before it has to be replated...as long as the bore isn't damaged. It is normally only .004-.005" thick on a stock cylinder, so there isn't much there. You will need to use a special hone to do it as well. A silicon carbide or aluminum oxide hone won't cut it.

  9. #9
    GoFastGuru's Avatar
    Join Date
    Jul 2010
    Location
    guntersville Ala
    Posts
    336
    +1
    8
    dont forget the heat factor steel sleeves get way hotter

  10. #10

    Join Date
    Jan 2006
    Location
    Texas City, Texas
    Posts
    1,249
    +1
    15
    Quote Originally Posted by MossBack View Post
    So can nikasil handle a hone with new pistons and rings or does it need to be replated ( assuming that the. Walls are not nicked) ?
    This is assumeing that they need to be honed at all. As RX951 explained, a bit of Muratic acid will clean any aluminum that happens to bond onto the nicasil after a mild seizure episode. In many cases, the etching from the original hone is still there.

Page 1 of 3 1 2 3 LastLast

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. Mixing nikasil and steel sleeves
    By butterbean_29512 in forum Yamaha PWC Performance (2-stroke)
    Replies: 1
    Last Post: 08-04-2016, 09:27 AM
  2. Replies: 5
    Last Post: 06-15-2012, 01:07 PM
  3. Yamaha GP1200R - Steel Sleeve vs factory sleeve
    By D88827 in forum Yamaha PWC Performance (2-stroke)
    Replies: 6
    Last Post: 01-21-2012, 02:27 AM
  4. Nicasil vs iron sleeve
    By Philou548 in forum MSX/Matrix
    Replies: 5
    Last Post: 10-02-2011, 01:49 AM
  5. stock wear ring rxp-x vs steel??
    By IM2FAST4U in forum 4-Tec Performance
    Replies: 14
    Last Post: 01-10-2009, 08:32 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •