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Greywolf55.... Tks for sharing. Awared how it's done, have performed 6-8 times, each time got my wife and children to assist. Sadly tire hang on air, bike weight and with my weight, A,B,C gives me almost same (1-2mm), which puzzle me if indeed my spring is too hard, got my wife and children to sit pillion, diff is 2-4mm.

Have adjust the spring from 20% to now 50% gives same sag results. Huh!!! Dunno what exactly is the issue.
 

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Found it Boy Racer.. YSS-46-20-30-220.
OK here's what this code means:

YSS: Manufacturer.
46: Spring ID Correct for our bikes.
220: Is the total length of the unwound spring. 220mm is used for 360mm shocks.

The important parts are the two numbers in the middle these mean the following:

20: This is the spring rate of the smaller softer coiled part N/mm
30: This is the spring rate of the larger part of the spring again calculated in N/mm

YSS use dual rated springs.

I'll be back shortly with another post detailing why these are totally unworkable for somebody of your weight.

Back soon........
 

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OK I'm back:

YSS-46-20-30-220 Your springs
YSS-46-17-25-200 The spring rating from my 340mm YSS shocks (note the lower overall length as shorter shocks)

My understanding when I bought my YSS shocks was that my spring rating was set-up (ready to ride) for a rider weighing in at between 12 and 15 Stones. That's around 76kgs to 95kgs.

This information is from YSS and one of their (so called) top UK service centres.

I weigh in with gear on just about dead centre between the 12 to 15 Stone range given by YSS and I trusted their superior knowledge and judgement in these matters - Big mistake!

These shocks were way over sprung for me at my weight a very harsh ride no matter what I tried, they also topped out which is worse than bottoming out.

Now onto your shocks:

At your stated weight of 60kgs + (9.5 Stones) even my springs wouldn't have worked for you as I'm 50% heavier than you and mine were badly wrong. You have springs that are 20% heavier compared to mine so they are not going to move under your weight and I very much doubt they move under the bike's weight either. Which is really what you've found out already.

My Suggestions for you:

  1. Unload all the pre-load from both shocks. You know when this is achieved as the spring will be fully extended and move up and down freely.
  2. Now wind the pre-load back on until it just touches the spring and then do one complete turn and stop.
  3. Set the rebound on both all the way to zero or 1 whatever it's lowest point is anyway.
  4. Now remove one shock from the bike either side will do - left is easier for the scrambler.
  5. To check sag I prefer to see how much movement there is it the shock itself rather than some place on the bike. This is easy to do by simply moving the rubber bung/stop down the shaft it then moves when the bike weight is on it and then again with the rider as well. But do whatever you're happiest with.
  6. Now with only one shock fitted see if you can get bike sag and then (carefully) get on and see if you can now get rider sag as well.
  7. If you get both (very carefully!) see if you can bottom the single shock out.
What I'm trying to see here is whether or not a spring half your current rating is strong enough or not, or even maybe too strong but I doubt that.

Please let me know how you get on and we'll take it from there.

Good Luck.........
 

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OK I'm back:

YSS-46-20-30-220 Your springs
YSS-46-17-25-200 The spring rating from my 340mm YSS shocks (note the lower overall length as shorter shocks)
Thanks so very much again Boy Racer.. my thoughts too the spring might be just too heavy for me. Will surely try to check the sag with just one shock.

trying to understand the mechanism why it’s so rigid, other than the dual shocks, my Immediate fear would be the swing arm bearing that might/could have friction or run out of grease.

will try the one arm shocks test in he coming weekend and report back.

cheers.
 

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will try the one arm shocks test in he coming weekend and report back.
Let us all know how you get on - remember to totally unload the spring and rebound beforehand to get a true idea if this spring rate would work as you can readily buy YSS springs at half your current ratings YSS-46-10-15-220 which may well work for you.......
 

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Let us all know how you get on - remember to totally unload the spring and rebound beforehand to get a true idea if this
Boy Racer....came back early today, first thing to do is the bike...

1. Bike on center stand with a 3cm plywood to ensure complete free rotation
2. Rebound wound to 0 and spring loosen(unload) to freeplay
3. Remove the left side shock.

Measurement of the right side shock results as follows:

A - bike on center stand free wheel play - 32.2cm
B - Bike weight (got 2 person to stable it) - 25.2cm
C - with rider 60kgs - 22.8cm

might sound stupid, when the bike off the center stand, so happy to see it lower down so much with just 1 shock as compare to 2 shocks = no difference.

If its the spring that gotta change, have today called up local YSS distributor, they do not carry spring, only the full product shock, hence have to order.

Will now install back the original shock (hv never feel using the original shock) while await what is the next step.

Thanks a Million in Advance.
 

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OK try your stock ones, how long are they? I'm not sure what model you have?

Your YSS are Scrambler/Thruxton length, stock on other models are 340mm which may be better for you as I'm guessing you're not a tall guy? I went down to that length myself.

My guess is you'll find the stock ones really harsh at your weight but give them a try on the lowest pre-load setting if only for the height test if nothing else. Only start spending money on the YSS shocks if you like the extra height of them.
 

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OK try your stock ones, how long are they? I'm not sure what model you have?

Your YSS are Scrambler/Thruxton length, stock on other models are 340mm which may be better for you as I'm guessing you're not a tall guy? I went down to that length myself.
Managed to installed back the ori, the bike is much lower, as usuallty on YSS with double stand, back wheel just touching the ground and no freeplay, the ori on double stand, there is maybe 3-5cm gap. did a short ride only as want to make sure have screw all in place.

am 178cm with inseam of 77cm, will be trying out tmw on longer distant. did some search, YSS have:

46-13-18-220, 46-10-15-220, not sure if these would be too soft. try the spring calculator, i got 0.75kg/mm ! huh, dunno what it meant for me.
 

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46-13-18-220, 46-10-15-220, not sure if these would be too soft.
46-10-15-220 would be the same total strength as your test which from what you said probably took up all the total travel of the shock without any pre-load, did you feel it bottoming out? The other option 46-13-18-220 may have worked for me (one step down from mine) but I never tried them.

Let us know how the stock ones go - the first thing to decide is whether you like this height or want to continue with the longer YSS shocks.
 

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46-10-15-220 would be the same total strength as your test which from what you
Thanks advise once again. Did about 150km today. I might be the opposite, the stock feels better in terms of comfort.(adjust to softest) We have lots of speed bump here and can feel the absorber actually works for the first time.

In terms of height, yes, would prefer the YSS length. The stock I can plant full flat feet, YSS - wud say about half of feet, not tip toe but comfortable. Will ride with stock and will check out the replacement spring price, if reasonable, will get one pair.

Once again... Thanks.
 

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Glad to be of help. I personally like being able to flat foot down as I find these bikes a little top heavy, makes it a lot easier paddling the bike around also, but a lot of folk like the longer shocks.

Here in the UK a set of YSS shocks springs are just over £40 GBP for the pair, that's via eBay take a look:

YSS Black Progressive Twin Shock Springs 46-10-15-220 8858803478975 | eBay

I personally would try the 10-15's out first, you could do some ('1 shock') testing using the pre-load adjuster to see if you can get the correct sag if you can without added a massive amount of pre-load on one of your current YSS shocks it would be a good indication that the lighter springs would work for you.

I no longer have a YSS to look at but I seem to remember that changing a spring out looked quite straight forward especially as you can take all the pressure off the spring by just unwinding the pre-load adjuster.
 

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Just remove and clean rear brake caliper, since it's raining, put it on center stand to just test the brake while on engine running. When I look down, to my horror I notice my wheel not align or more like slight wobble. Tire issue, rim issue or just mis-align?

No wonder I can't take sharp corner even at slow speed as feel rear is not gripping /implanted to ground and blame on the shocks (which actually is hard too).

Will visit the tire shop to hopefully is an alignment issue.
 
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