R6 update on R6 rod bearings.

Discussion in 'Tech' started by Vinnie@proline, Nov 9, 2007.

  1. Vinnie@proline

    Vinnie@proline Well-Known Member

    I have just found out that the specs are incorrect :wow: and there is a new format to findng the correct rod bearing. I had seen this information on the Yamaha Dealer website today. As soon as I copy the info I will post up. :beer:
     
  2. PC_Geek

    PC_Geek Well-Known Member

    Any luck on this? I can not seem to find that data. Thanks
     
  3. TwoCycler

    TwoCycler Well-Known Member

    It's not the rod bearings, but the main bearings. The tech sheet said to subtract one more from the main bearing final numbers. So where you would have used a 4 use a 3. This is really irrelevant as you should measure the clearances anytime you swap bearings. I have seen since the first 2006 R6 I built that if you go by the marked numbers on the cranks/cases/rods that the rod bearing clearances are a bit on the tight side and the main bearings are on the loose side. As the clearances get looser, oil pressure drops. If the mains are loose, it drops the pressure to the rods and you could seize a rod bearing, even though the rod clearance was acceptable. I measure all mine and have never had a bearing problem on the R6...

    Rocky Stargel
     
  4. Chip

    Chip I hate it.

    Ahhhhh....the miracle of Plasti-guage...
     
  5. d-wire

    d-wire Well-Known Member

    yep, no more lower end problems ...me likey, and so does my wallet
     
  6. WERA872

    WERA872 Well-Known Member

    the only formula I have ever used is the measurement formula. I dont even look at the #s or letters any more. The last 07' R6 I built took 13 of the same part # rod bearings to find 8 that measured the same. The average dealership or individual that would have tried to use these bearings going by the factory codes would have definately had a spun rod bearing very quickly. The smallest of the bunch would have given .0008" clearance.
     
  7. Handicapped Racer

    Handicapped Racer Well-Known Member



    :crackup: This says it all.
     
  8. Handicapped Racer

    Handicapped Racer Well-Known Member

    :wow:
     
  9. Chip

    Chip I hate it.

    and this is why you shouldn't have your race motor build by a dealership.
     
  10. 418

    418 Expert #59

    Agreed 100%.

    Your average dealership tech simply does not have access to tools nor the experience in building performance motors. Everyday, all day long. You've got to live and breathe this stuff to make a difference on these motors.

    As for clearance issues though, we could have seen this coming. Had a similar issue with a '05 {yes a '05} that was exactly what WERA872 is talking about. Right packing, right part {supposedly}, wrong clearance.
     
  11. Handicapped Racer

    Handicapped Racer Well-Known Member

    a dealer by me rebuilt a 04 1000 dynoed it after 139 hp:crackup:. Took it apart re-rebuilt it lol 170.0 after it was all said and done.
     
  12. ed who?

    ed who? the opposite of eharmony.

    agree with all. The clearances when MEASURED are NOT what the "book calls for" which i was like "hmmm...strange..but ill trust my measurements"

    We have still seen issues, i have seen personally 4 bone stock ones that spun bearings (some mains, some rods) so its an issue stock even for sure. what is it i learned long time ago "measure twice, assemble ONCE" lol
     
  13. Turbotech

    Turbotech Well-Known Member

    50 cents of plasti-gauge goes a long way.....Hell they make the stuff for a reason..
     
  14. humblepie

    humblepie Well-Known Member

    I am curious to know how much oil pressure these engines generate oem at, say 100 degrees C., oil temp.
    I realize the pressure will vary with viscosity. Anyone know off hand?
    I have no lower end experience with the latest R6.
     
  15. Handicapped Racer

    Handicapped Racer Well-Known Member

    Did you tell corey about that!
     
  16. HFD1Motorsports

    HFD1Motorsports BIKE TUNA

    make sure you are looking at the rod big ends...I am seeing some bigger ovals
    in the r6...
     
  17. Orvis

    Orvis Well-Known Member

    Do you really use plasti-gauge?
    Over the years I have tried plasti gauge a few times and compared it to the measurements achieved using micrometers and found the plasti gauge to be, at best, an educated "guess" as to what the clearance was. When you're spinning an engine up in excess of 12 or 14 thousand rpm everything had better be correct. I'm serious, plasti gauge just doesn't cut it unless you're working on a Briggs engine.
     
  18. theQman23

    theQman23 Racer's Choice for TIRES

    As for Mr. Orvis' comment, I sometimes agree but it depends. Using very high quality mic's then yes, that is all that's required. But I've seen dealership mechanics using low quality measuring tools with a lot of slop in them. The micrometer is only better than the plastigauge if it costs more than twenty bucks, (which I'm sure your using, but this is a public forum so the person reading this may not be,) so if the person reading this goes and uses a harbor freight tool, then he would actually be better off with the plasti gauge, it would be more accurate.
    -Quentin
    Mize Mobile
     
  19. Chip

    Chip I hate it.

    The you are using the Plasti-Guage wrong.

    We use Plasti-gauge and micrometers to build all the "briggs" engines that come out of our shop..... I guess we will all have to go in the back and kill ourselves now. :(
     
  20. Chip

    Chip I hate it.

    If you are using a $20.00 harbor freight mic to assemble a modern race motor, then it is going to blow up anyway, because that means your a cheap ass and you skimped on something else important.
     

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