What have you set your front compression too?

Discussion in 'Maintenance' started by tgosai, Aug 16, 2013.

  1. tgosai

    tgosai Member

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    Hi
    My front compression is set at 1.5 turns in from full (factory standard is 2),I'm thinking of turning it in by .25 or .5 click in so it's 1 or 1.25 away from full.

    How harsh would that make the ride ?

    The reason I ask is that when I give it full gas for a short burst and then quickly hit on the brakes hard, it dives in a little and even makes the ABS brakes fade for a split second but come back in and appy full force to the brakes.

    So it got me thinking it could be due to too much compression settings and maybe turning it in may help.

    What do you think and what have you set yours at ?
     
  2. ShinySideUp

    ShinySideUp Elite Member

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    Best advise i would give is try it and see what you think of the setting?:D

    There is no magic setting when it comes to suspension setup, it's like tyres everyone has different opinions on the same thing! So again best you try adjusting the settings yourself and go for a ride and see what you think. If you don't like them you can always put them back to where they are now!
     
  3. Kentblade

    Kentblade God Like

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    I haven't got a clue what it is set to, even if the first owner changed it or even if he was a pork pie advert and screwed it......it still goes where I point it at any speed, that's all I ask for in a bike.

    Not scientific I know, but it works for me.
     
    #3 Kentblade, Aug 16, 2013
    Last edited: Aug 16, 2013
  4. Only1Matrixxx

    Only1Matrixxx Active Member

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    Just so you know when you talk about compression damping, you would usually say it is 1.5 turns OUT from full hard, not in. This becomes an issue when you talk about relative movements, such as your .25 or .5 turns IN to make it harder...
     
  5. Escargot

    Escargot New Member

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    When I first bought my bike (2008 RR8) a couple of months back, I took it into my local dealer to show it off. Their chief mechanic asked if he could take it out for a ride (sure, why not) and when he came back, he said he thought I should check the suspension settings as it wasn't turning in as well as they should. I wouldn't have had a clue as, unlike him, I don't ride different bikes every day. Plus I never normally fiddle with these things. Anyway I got home, checked the manual and carefully reset every suspension setting to the original factory setting (they're all listed in the manual). The instructions were really clear (I'm no mechanic) and the whole exercise took c30 mins.
    Result? A massive noticeable improvement in the bike's handling.
    If you're unsure, I'd strongly recommend this as a good starting point.
     
  6. Slick

    Slick Elite Member

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    I have an ABS also and can find a similar thing but only when it the weather gets really hot or say at the end of a trackday. I need to increase compression a tad, no more than quarter turn. I am currently 1.75 from full hard go to 1.5 on a hot day.

    When cold a find 1.5 (from full) a little too hard so I always return to 1.75 at the end of the day. Maybe I need to refresh my oil or change the weight?
     
  7. tgosai

    tgosai Member

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    thanks Slick, that's good to know. I'll give it a quarter turn and see how it goes.

    and thanks everyone else for the feedback.
     
  8. tgosai

    tgosai Member

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    one more thing, seeing that compression needs to be dialled in a fair bit, would that suggest the fork oil needs topping up or changing ? my blade is 2010 and done 6k miles
     
  9. Slick

    Slick Elite Member

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    Mine is a 59, has 22k on the clock and gone on a few trackdays, this bike is a keeper though and my plan is for it become my track bike when I next upgrade.

    Like I said I only really notice this in the hot when purposely activating the ABS, do the same in colder/wet weather I don't get the diving and much better braking (when the ABS takes control) - the better way round I guess!

    You will notice the rear shock also gets cooked, but I don't really notice performance changing as it gets hotter.

    Once I have some spare cash I will either buy some BPFs from the newer models or upgrade the internals to K-techs or something similar.


    EDIT,

    Had a leaky seal a few months back so the oil is pretty much brand new( in one of the legs anyway!)
     
    #9 Slick, Aug 16, 2013
    Last edited: Aug 16, 2013
  10. samd1985

    samd1985 Active Member

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    I would say your assumptions are probably correct mate given that you feel your ABS is kicking in early.

    Looking at it from a practical pouint of view: you're accelerating; so the forks are extending out, probably fully. Then, as you transition quickly to the brakes the weight of you and the bike moves forward. The forks begin to compress, along with the tyre squishing into the road. If (as likely in your case) compression is set too stiff, i.e. preventing the forks compressing, the suspension will resist the forward weight transfer as the forks won't dive enough, preventing the weight loading up the front tyre, thus creating a 'skid' (where the ABS system kicks in).

    1/4 and 1/2 turn adjustments on the <2012 non-BPF forks makes a noticeable difference. On my 2012 with the Showa forks there's very little noticeable change even after a full turn as the range of adjustment is much larger, but there's less of an extreme at each end of the scale.

    To put it simply compression damping controls two things: the rate of dive under braking, and control of the front wheel over 'positive' bumps:

    Too soft and it'll dive sharply under braking; possibly causing loss of traction at the rear and potential bottoming of the forks. Over bumps, it may also cause the front wheel to continue its upward journey past the top of the bump and lose contact with the road momentarily as the bump drops away.

    On the other hand if it's too stiff the front will resist diving and not allow the front to 'load up' to give maximum grip under braking, and also every bump in the road will be transmitted through to the chassis to the rider giving an unnecessarily harsh ride.

    A myth is that stiffer suspension handles better... This generally is not the case, and as most have already mentioned there is no 'ideal' setting - just one that works for you, and that can only be worked out by testing and adjusting. Ideally, you want to soften it up as much as you can get away with; i.e. soft enough to allow the front to dive positively and soak up the average bumps that you encounter, but without bottoming out under hard braking or being too soft that the handling is like a boat! Track bikes tend to have stiffer settings because A) braking is always at maximum effort, and the primary job of compression damping on a track bike is to control dive at the front. B) As there are very few bumps on most tracks, unlike our glorious UK roads, this setting can be stiffened to control 'A' as there is no real concern over plushness of ride.

    Ok, i've gotten carried away, but hopefully it all makes sense?! I set up a friend's 2011 blade on a recent trip but cannot remember exactly what the compression settings were, nor any others for that matter! What i do remember is that i softened the front preload to 3 turns in from fully soft to assist cornering (lady rider, quite light, and cable ties around the fork stanchions showed a good 15mm remaining of travel after this and some decent, all-out braking!), and compression damping was somewhere on the softer side of the mid-range between fully hard and fully soft. Perhaps around 2 turns out from full hard? I can't be certain though. i know it wasnt miles from the standard settings though which she had on before. I remember slowing rebound by 1/4 turn from her 'stock' settings (going by the verbal confirmation that she'd physically set them to stock when she bought the bike).

    The best advice for yourself would be to turn it right in to full hard until it seats lightly, then back the adjuster out until it again seats lightly in the full soft position. Don't over-tighten it when you seat it - be gentle! I think it's around 3 1/2 turns of range from memory. then, adjust the setting so it sits bang in the middle of full hard and full soft. See how that feels. Take a bit of time to get used to it and perhaps even write down any differences you feel. If you want, you can then experiment by softening or hardening by 1/4 of the range in either direction and ride it again to feel the difference. I suggest a 1/4 of the range as that'll give you a noticeable difference. 1/4 turns may be hard to feel any improvement. See what you prefer. Take a notebook and record the results.

    Remember: You can always revert back to standard if you dont like the changes. Thats the beauty of adjustable suspension ;)

    Essay over!

    Sam
     
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  11. ShinySideUp

    ShinySideUp Elite Member

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    Hey,
    Fork oil just like engine oil does require changing every now and then.
    Depending on who you speak to you may hear different answers as in the case of racers they tend to be at every race, ohlins recommend every 4k miles for there forks but manufacturers seem to have settled around the 7.5k miles for road use forks.

    Every time a fork extends/compresses to obsorb bumps and brake dive the springs inside scrape against the fork tubes and small metal particles are scraped off and gather in the oil. Eventually these particles can turn the oil into a sludge which can clog the damping system holes reducing the ability to work properly.
     
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  12. tgosai

    tgosai Member

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    Thanks Sam, a very concise write up
     
  13. Slick

    Slick Elite Member

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    Interesting write up Sam!

    Like you said there is no ideal setting. I found at 2 from hard my forks where close to bottoming out on heavy braking and felt too soft.

    Got mine set up by Parkitt racing on a trackday and found the stock settings a little soft and 'wallowly' therefore both comp and rebound where hardened a bit.

    On the road I do run with my pressures a little lower than recommended, as I said I do feel the suspension getting a little softer when it gets too hot ie the fronts diving a bit more hence stiffening up a tad, didn't think to go the other way to see if there was any improvement, - might give that a go
     
  14. sinewave

    sinewave God Like

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    OP, It's always handy when posting these types of Q's to actually let us know what model/year or Bike you have?


    What's settings are good on my BPF MY12 will not suit a MY08-11 Blade or a 04-07 Blade!


    The Devils in the detail as always! ;)
     
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  15. samd1985

    samd1985 Active Member

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    It's always worth trying different settings to see if there's an improvement, but only adjust one at a time and ride the same circuit so the differences can be compared. After all, how do you know what bad or good feels like until you've experienced it...

    I took someone's advise a while ago where they suggested setting rider sag to 30mm rear and 35mm front. For me, that meant setting the rear preload adjuster on 7/10 (10 being hardest) and having front preload set at 12 turns in from fully soft... Compression and rebound were left as stock. The bike felt awful!! It was bucking me out of the seat and taking off over any bump I encountered, not to mention being hard to steer and the forks topping out with even fairly gentle acceleration. I was only using 2/3 of the suspension travel at the front too.

    The most important setting to get right first is the sag, and the rear is the one where it matters most. I aim for 35mm rider sag for road use (30-35mm is the general recommended range) and around 30mm for track, but rarely stiffer than that.

    For the forks I aim for somewhere around 40-45mm sag and then use a cable tie around the shiny part of the fork to check how much travel remains after hard braking/stoppies and general riding, ensuring there's 10mm minimum remaining before bottoming out, shown by where the cable tie ends up. Add or remove preload to ensure there is 10-15mm of travel remaining over and above what is encountered If you can get the front sitting a little lower by keeping preload to a minimum the bike will turn in better, and the ride will be plusher as bumps will be absorbed. Then, it's time to adjust the rebound rates, followed by compression.

    As you've noticed Slick, warm oil flows better than cold, so a small adjustment towards stiffening or 'slowing' the damping is likely to be required. Also important to set up the suspension's damping after having a good ride on the bike to warm the oil up. I also run tyre pressures lower than standard 36/42 and much prefer it :)

    Sam
     
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  16. Escargot

    Escargot New Member

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    Following various posts on here, I contacted Sam (a really nice friendly guy) and, since I live in his general vicinity, arranged to toddle over to his to see if he could work some magic with my 2008 RR8. Having previously reset my suspension to standard settings per the handbook and found that a big improvement, I was a tad sceptical that he could do much to improve things further. Indeed, after prodding and bouncing it a few times, he did say it was already not too bad. However, he spent well over an hour on it, getting me to sit on, get off, sit on and get off it a few times before he was happy.
    I took it out for a social run to the Cotswolds yesterday - 190 miles round trip. And there is a subtle but noticeable improvement, mostly in the way the bike feels more intuitive to me, as well as being a more comfortable ride. Turn in is more confident and holding a line in a corner feels more secure. These are subtle and necessarily subjective observations since I haven't sufficient technical knowledge or experience to provide anything more analytical. But I hope it conveys the impression that, even if you're not a track god, you can still derive great benefit from having your suspension set up correctly to suit you personally. And the great thing about the Blade is that so many of the suspension settings are adjustable (unlike other bikes I've owned). So it seems a waste not to take full advantage of that.
     
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  17. ccr32

    ccr32 Active Member

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    Another thread that I have found and resurrected (sorry!) but something else I have noticed about my bike, which I admit is probably beginning to sound like a complete pup based on my various posts about issues, but really it is just that I am a fussy bugger...

    The BPF's clonk quite badly on certain road surfaces, or when inadvertently hitting a drain or pothole. I believe this is normal, and the brand new demonstrator blade I rode before buying mine also did it, so I presume it is just one of those things...

    This post below from another thread also suggests the same:

    I was wondering if adjusting the rebound settings would help with this, as it feels to me as if the clonk noise happens when the forks top out.

    Thoughts?
     
  18. RedMacGregor

    RedMacGregor Active Member

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    I've always noticed the same clunk early on in the ride but once I've go going it seemed to disappear however I've just had my forks serviced and I know they have used thinner oil and the clunking is happening more often. I always thought the cluncking became less noticable because the oil thinned up and moved through the shim stacks with less effort but I'm not so sure now as using my theory it should be better with thinner oil. That said it was only just above freezing when I went out for a test ride so the oil could be quite thick.
    I'll give the company that serviced the forks a call and find out if they know what the cluncking is.
    Cheers - Steve
     
  19. exuptoy

    exuptoy Elite Member

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    An old thread but an interesting read above @samd1985 .
     
    #19 exuptoy, Jul 20, 2015
    Last edited: Jul 20, 2015
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