Bit of a predicament - Racetech springs with Andreani cartridges

Discussion in 'British Beasts: Triumph Tigers' started by YIDDISH COWBOY, Feb 11, 2019.

  1. YIDDISH COWBOY

    YIDDISH COWBOY Stuntman

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    I've had issues with my andreani cartridges. They've always felt way undersprung. Today I opened up my fork tubes to replace the springs with Racetech 1kg, put 7w fork oil and new fork seals in.

    Couple things...the rebound cartridge had unscrewed itself from the cap...that explains a lot. I was easily able to replace the fork seal without a seal driver. Made me think I was doing something wrong but I think it's fine.

    The racetech springs are much shorter than the stock but longer than the andreani. I'm not sure how to reconcile this. I (with great effort) got the RT springs on the AD cartridge (one of them, didn't have time for the other).

    I could cut the AD spacer but it's pretty product-specific and wouldn't be a simple job.

    From left to right: stock spring, RT spring, AD spring, Stock Cartridge, AD Cartridge
    [​IMG]
    #1
  2. clawdog60

    clawdog60 Long timer

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    I can see why. More cartridge than spring. Adriani is going with valving opposed to spring rate.
    No travel loss?
    #2
  3. akaDigger

    akaDigger Amateur Adventurer

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    I have general experience with RaceTech so I was interested in in your "predicament". I am not clear on what you have already done as in "with great effort". Your description kind of leaves me to think you are installing the RT spring in the same location that the Andreani spring was, between the top of the cartridge and the cap. Have I assumed incorrectly? Also, what model Tiger and year are you working on? White power or Showa? I do not recognize the stock cartridge since my experience is with 2011-14 800 Roadies and XCs.

    That RT spring was meant to sit at the bottom of the stanchion, as the stock spring did, surrounding the lower cartridge and pre-loaded with a long spacer tube up to the cap with a washer between spring and spacer. The pre-load should have been no more than 10mm, probably less. My guess is that a 1kg spring set is way too stiff for any Tiger as the stock rate is less than half that for a 800.

    You felt the bike was way under sprung. Could you elaborate? With one rebound valve/piston unscrewed, you were essentially working with only one fork. The rebound valve acts as a piston on the compression stroke so if it were not screwed to the cap, you would have no piston to push oil through the compression valve mounted at the bottom of the cartridge. There are also other reasons for a front end to feel under sprung even if the cartridges were intact.

    On the older 800s, the fork seals do not fit extremely tight either. I have removed them with no damage and then reinstalled the removed seal with little effort.
    #3
  4. YIDDISH COWBOY

    YIDDISH COWBOY Stuntman

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    Yes. I am familiar with all those words. I ride a 2013 Explorer 1200. I'm 210lbs naked. Factory springs were very mushy and easy to bottom out. Andreani springs were even worse (and the rebound cap wasn't loose when it was installed).

    I installed the RT springs as they should be against the lower stanchion with the Andreani spacer in place between the spring and cap. I just finished the 2nd fork and I'm about to install it. I expect it to be WAY too stiff because the springs are about 2" longer than the Andreani springs and as installed, that means there is about 2" of preload on them right now.
    #4
  5. akaDigger

    akaDigger Amateur Adventurer

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    Sorry. I had assumed that the Andreani springs fit up top between cartridge cylinder top and cap as many Andreani set ups do. From the photos you posted above, it looks like that would have been the case here.

    In general, I can tell you that you will likely have very little, if any sag with the installation at 2" of pre-load. In contrast, my 800XC had only 1.8" of sag (I was looking for 2.9") with .80kg RT springs and only a few mm of preload. I have since gone to .65kg RT springs. The un-sprung weight of the Explorer is probably not that much more than my XC. Two inches of pre-load = 110lbs. Set the weight of the bike on the forks and it will compress 1mm more for each kg of weight over the initial 50kg.

    As far as bottoming out, my stock .49kg springs never bottomed out. However, upon initial installation of the much heavier RT .80kg springs it would. Front end dive was extreme. The RT recommended oil level was hell and gone from stock. I solved the problem by measuring the oil level with the stock springs IN. About 40mm compared to Triumph manual recommended 107mm with springs OUT. I put the RT springs in, purged the cartridges and filled to the same 40mm level, replicating stock. This is different from your case but what is the same is that a higher the oil level, the more resistance to bottoming and diving you have. While the springs have a lineal rate, the air "spring" is progressive".
    #5
  6. YIDDISH COWBOY

    YIDDISH COWBOY Stuntman

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    I gave up and put the andreani springs back in there. Might be time for a new bike.
    #6