675.cc • Triumph 675 Forum

SAG and Preload

Discussion in 'Maintenance & Tweaks' started by Godzilla, Dec 7, 2009.

  1. Godzilla

    Godzilla

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    Just wondered if any of you have set the SAG by adjusting the preload on your 675.

    Out of interest I measure the bike only SAG of my front forks yesterday and it came out at 15mm.
    Now Im nowhere near as heavy as my bike so i dont think with me on the bike it will come anywhere near the recommended amounts of 30mm for track and 35mm for road use.

    Seems a bit odd to be putting a bike out with such small SAG

    Anyone any thoughts?

    Cheers
     
  2. i have one thought....wtf are you on about :lol: :lol: :lol:
     
  3. D41

    D41

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    "Sag" is the amount the suspension compresses with the rider seated on the bike, Nige - most bikes come set up to accommodate a rider of typical/average weight - around 11.5 stone.
     
  4. gotcha, thanks D...ILL GO STAND IN THE THICKY CORNER :D ..im 14 stone, what should i do with my suspension and how do i do it?
     
  5. D41

    D41

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    Nothing!! - Unless you are having difficulties with your bike's handling then there's no need to do anything...if, however you are doing trackdays and/or riding hard on the street I would recommend stiffening up the suspension to compensate for your extra 'healthiness'. - TBH, I'm no expert on suspension set-up, but this strikes me as the most obvious approach.
     
  6. Simple, easy to follow PDFs on getting the sag set correctly can be found here

    http://www.feelthetrack.com/tuning_guide.htm

    only need a friend and a tape measure.

    Personally I would at least get this set up correctly, even if you have no major problems with the bikes handling, as it will improve the handling.
     
  7. Godzilla

    Godzilla

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    Starting figures for SAG should be around 35mm for road use and 30mm for track use.

    Mine is miles less that 30mm as standard from the factory, and nowhere near enough preload adjustment to get it close to those figures, without changing the springs. Sucks imho.

    Agreed panoptikon, it should be set correctly. Wonder why this isnt a service done when u pick the bike up from the dealers. Surely wouldnt take them too long.
     
  8. They don't even bother setting the chain tension to suit body weight so they're never gonna sort suspension!! Spending that amount of cash on a new toy you would think a little bit of time with the resident mechs would be thrown in to get the bike fitted to you!!! They can't do enough for you until you hand over the cash!! I agree with the comments above setting up to suit you makes a difference, take a look on the net for instructions and get a mate to help you and remember to write down any changes made so you can revert back to where you started. Use a zip tie around the front fork to help you measure the sag.
     
  9. thanks all, :smileup: thats my weekend sorted out...the bike is a bit twitchy in corners but ill see what its like after ive fiddled with it :D
     
  10. Godzilla

    Godzilla

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    Nige will you kindle swap your avatar, Im having real problems concentrating on the threads you post in :roll:
     
  11. NO..the pic is far more interesting than anything i have to say :lol:
     
  12. ok, i gave in...do you like the new one.. :lol: :lol: :lol:
     
  13. Godzilla

    Godzilla

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    :shock: Hmmm let me think about that Nige , may take a millisecond YES :lol: :lol: :lol:
     
  14. Godzilla

    Godzilla

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    Hmm just measured the rear of the bike.

    Unweighted 552mm

    Bike (no rider) 447mm

    That means bike weight gives 5mm of SAG. Bl(*&*dy hell, how fat would I have to be to squash that spring 30mm for trach use or 35mm for road use.

    By my basic maths I would need to be over 1 tonne :(
     
  15. Better get started on those mince pies then.

    Being serious, it is unfortunate but personally I try to see it from Triumphs perspective, if your going to release a bike the suspension has to be ok (ish) for all weights plus a pillion. This will never be ideal for our purpose. It would help a lot of people if the dealers took a few minutes to prep the bike with their customers. Still deciding how far I need to go to on mine, almost certainly doing the fork internals though.
     
  16. henrymc

    henrymc

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  17. Godzilla

    Godzilla

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    I've booked in to these guys tomorrow morning

    http://www.kais-performance.com/

    £40 to fully set up the bike suspension, will let you know what they say about the springs and settings and stuff :)
     
  18. Godzilla

    Godzilla

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    Just got back from Kais. They said my bike was setup miles out from where it should be. Too much sag at one end not enough at the other. At the front there were 3 rings of preload, they have more than doubled that. The also said that the number of clicks of compression and rebound damping were miles out and different in each stanchion. Not really tested it yet, due to wet roads and numb fingers due to cold, but it did tip in faster and seems more stable mid turn.

    In fact they told me that the new Ducati dealers in manchester now give a voucher for a setup with him with every new bike sold. He didnt try to sell me any parts even though I asked if it would benefit from upgrading.
    Am quite impressed.
     
  19. nice one godzilla, hope it was worth the money..ill have to see if theres someone offering the same service down this way...let us know how you get on with it would you mate
     

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