chain slack

Discussion in 'Performance & Technical' started by stryder85, Aug 3, 2017.

  1. stryder85

    stryder85 n00b

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    Would 1.5in - 2.0in of chain slack get me thru tech. I just don't want to be adjusting at the track if I can avoid it. Thanks
     
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  2. Prufrock

    Prufrock traffic

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    Yeah, I think that would pass without question. So long as it doesn't flop around or risk jumping the sprocket.
     
  3. stryder85

    stryder85 n00b

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    Thank you
     
  4. VernLux

    VernLux Knows an apex
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    The amount of slack in a chain is a somewhat elusive number. One thing is for sure though, there needs to be at least some slack all the way through the full travel of the rear suspension. The thing is, if you weigh 140 lbs and will never fully compress the rear suspension travel, you might get by with a little less slack than say a 215 lb rider who may come a lot closer to fully compressing the suspension. When I'm doing tech inspections during the morning before a track day, if the chain seems to be a little snug, I will generally have the rider sit on the bike and then see how much chain slack it has. I've seen chains tighten up so much when the rider gets on the bike that the chain could double for a banjo string. When a chain is that tight, it will impair the suspension to the point that it will not allow for full suspension travel. 1.5 to 2" seems a bit excessive, but barring the chain being so loose that it could possibly come off, looser is better than tighter. Hope this helps a bit.
     
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  5. stryder85

    stryder85 n00b

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    I think the manual says 1.77in being the loose end of range. So should be good for my 190lbs.
     
  6. VernLux

    VernLux Knows an apex
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    If you can find someone to help you, sit on the bike and have them check the slack. Try to slowly bounce on the rear as much as you can and if they feel the chain get tight, back it off a bit more. It's not the same for everyone, but then again, you definitely don't want it too tight. Good Luck!
     
  7. R/T Performance

    R/T Performance found track bike
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    Safe spec is 1.5" that's what I look for when I tech and set my own to
     
  8. TLR67

    TLR67 Knee dragger
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    Just remember when its smiling its Happy!!! The best way to ensure your chain is at correct adjustment was passed on to me from the late Tryce (TDubb) Welch.... At Barber one year I was installing a new RK on my GSXR... Tryce was there coaching Jake Lewis before his AMA Supersport days... When I got things buttoned up he showed me the steps below he always used when building bikes for Flatrack, Road Race and Dirt.... It made sense and I have always used this and honestly got over 5 Years of use on my last chain from doing it...

    1-Get your bike on the stand (Has to be on stand for correct specs)
    2 Adjust blocks but leave Axle loose.
    3- Take a regular screwdriver and put it on the teeth at the top of the sprocket under the chain
    4- Roll the wheel Clockwise
    5- When the screwdriver hits the 1 O'clock position tighten axle...

    If you change gearing you obviously have to change block adjustment. This was one of the best Mechanic tips I ever got honestly and will use it until I quit riding... RIP TDubb.... Thanks Dude...
     

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