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1Back to top Go down    rear shock issues - big time on Tue Jun 27, 2017 2:40 am

scottd

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Desperate to deal with aftermarket Progressive rear shock that came on my 91 LT. Its very hard on the passenger, has been adjusted all the way down, and I need to do something about it. Replace with something else, or find a stock rear shock to put on it. I'm over 6' so I don't need this lowered rear shock either. Does anyone have suggestions if there's some way to make this Progressive shock better, or if I should replace it - and with what - and rough idea of cost?? I'd really appreciate some suggestions. Thanks!!
Happy riding.

    

2Back to top Go down    Re: rear shock issues - big time on Tue Jun 27, 2017 3:40 am

RicK G

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Hi Scott welKome to the Knuthaus. Best thing with a progressive (they get progressively worse as the days roll by) is to feed it to a rubbish bin and get a RAM. I have 2 bikes with them and they are good http://www.realmengineering.com/page15.html


__________________________________________________
If everything seems under control then you aint goin fast enough:- Mario Andretti
Bikes 1986 K100RT, 1993 K1100 LT, 1994 K1100 LT, 1993 K75 RT, 1996 K75RT, 1986 K75 GS, 1979 Z1300 Kawasaki X 2 & 1976 SR 500 Yamaha for now
    

3Back to top Go down    Re: rear shock issues - big time on Tue Jun 27, 2017 7:12 am

duck

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I had a Realm/Ram on one of my bikes for a while. Their default was to spring it for 2-up loaded so it was very harsh at first but I bought a lighter (less stiff) spring from them for it and it was fine after that for one-up riding.

The stock shocks that came on Ks aren't that great and any one you find these days will most likely be worn out and bottom out riding two-up.


__________________________________________________
Current stable:
86 Custom K100 (K75C fairing, K75 Belly pan, Ceramic chromed engine covers, 32/10 final drive)
K75 Frankenbrick (Paralever, K11 front end, hybrid ABS, K1100RS fairing, radial tires)
86 K75C Turbo w/ paralever
93 K1100RS
94 K1100RS
93 K1100LT
91 K1
93 K75S
http://www.ClassicKBikes.com
    

4Back to top Go down    Re: rear shock issues - big time on Tue Jun 27, 2017 3:17 pm

Corkboy

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Another option is a YSS shock. A few of us have them. mine on a K1100, Olaf on a K100.

Cheaper than a RAM, and I have no complaints so far.


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Regards,

Corkboy '87 K100RS 0140995 (Gone)
'97 K1100LT 0188024
'08 Transalp 700
    

5Back to top Go down    Re: rear shock issues - big time on Tue Jun 27, 2017 7:37 pm

Dai

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Go for the RAM. As Duck says, anything OEM on the market is going to be fooked.


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'83 K100 upgraded to K100RS spec
Others...
'78 Moto Guzzi 850-T3, '79 Moto Guzzi 850-T3 California,'93 Moto Guzzi 1100ie California,
'03 Suzuki Blandit GSF600SK3 (NFS any more because wifey has claimed it)
    

6Back to top Go down    Big $ for rear shock on Tue Jun 27, 2017 8:59 pm

scottd

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Thanks everyone for the suggestions. $750 Canadian for a new stock BMW rear shock, $470 for a new Progressive 465 entry level / $750 for the upgraded model. Ram seems to be about same as Progressive entry level for price, and YSS a little more economical yet. Lots to consider, especially when considering my passenger!! Thanks again.

    

7Back to top Go down    Re: rear shock issues - big time on Tue Jun 27, 2017 9:38 pm

MIBrick

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@Corkboy wrote:Another option is a YSS shock. A few of us have them. mine on a K1100, Olaf on a K100.

Cheaper than a RAM, and I have no complaints so far.

Which model number is most common for the K100s? Specifically an 86 K100RS. Just looking for some guidance among the multitude of models and options they have..

    

8Back to top Go down    Re: rear shock issues - big time on Tue Jun 27, 2017 9:57 pm

RicK G

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There are several versions of the K100RS but essentially they are all the same it's only colours and decoration of stickers.


__________________________________________________
If everything seems under control then you aint goin fast enough:- Mario Andretti
Bikes 1986 K100RT, 1993 K1100 LT, 1994 K1100 LT, 1993 K75 RT, 1996 K75RT, 1986 K75 GS, 1979 Z1300 Kawasaki X 2 & 1976 SR 500 Yamaha for now
    

9Back to top Go down    Re: rear shock issues - big time on Tue Jun 27, 2017 11:13 pm

Laitch

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@scottd wrote:Desperate to deal with aftermarket Progressive rear shock that came on my 91 LT.
How have you gone about adjusting it?


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1995 K75T 60,000 miles
    

10Back to top Go down    Shock adjustment on Wed Jun 28, 2017 2:35 am

scottd

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I just unscrewed the adjustment collar as low as I could get it. I also pumped some air into it with a hand pump. Then let the air out of the shock. I can't get it to soften up. I'm thinking that because its the short shock it may never be that comfortable??

    

11Back to top Go down    Re: rear shock issues - big time on Wed Jun 28, 2017 3:52 am

RicK G

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Being a short shock the spring will be stiffer than the std length. The valve is to pressurize it with nitrogen which stops the oil foaming and gives it a small amount of lift.


__________________________________________________
If everything seems under control then you aint goin fast enough:- Mario Andretti
Bikes 1986 K100RT, 1993 K1100 LT, 1994 K1100 LT, 1993 K75 RT, 1996 K75RT, 1986 K75 GS, 1979 Z1300 Kawasaki X 2 & 1976 SR 500 Yamaha for now
    

12Back to top Go down    Re: rear shock issues - big time on Wed Jun 28, 2017 5:52 am

BobT

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@scottd wrote:I just unscrewed the adjustment collar as low as I could get it. I also pumped some air into it with a hand pump. Then let the air out of the shock. I can't get it to soften up. I'm thinking that because its the short shock it may never be that comfortable??
You need some air in it to make it a bit soft, the air is a cushion. No air would be rock hard as would a very high a pressure. Air compresses and oil does not. I would think that a hand pump is not going to do any good with shock absorber pressures as they are way higher than tyres.
My shockers on my microlight (230 kg empty weight) have something like 12 bar in them and you will never get to that with a hand pump.

    

13Back to top Go down    Re: rear shock issues - big time on Wed Jun 28, 2017 7:18 am

Laitch

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Is the shock mounted with the sag adjustment color end of the shock fastened on the lower mount or on the upper mount? How much is the average estimated usual passenger and baggage weight? Does this shock have the five position rebound adjustment wheel? What is its model number?


__________________________________________________
1995 K75T 60,000 miles
    

14Back to top Go down    Re: rear shock issues - big time on Wed Jun 28, 2017 8:38 am

92KK 84WW Olaf


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K manual gives max 200kg for added weight.

Two up with luggage and its safe to say you will well exceed that.

Weigh yourself in full riding kit, jacket, pants, armour in, gloves, boots, helmet on etc and the usual bag of coins keys smokes and whateverin the pockets. Do the same naked and you will see the difference will be about 15kg. Now few of us if any are below 75kg and looking at photos on the Harley forum would suggest starting with 100-120kg plus the 15kg would be realistic average.

I hit 90kg ready to ride and I suspect average is nearer 115-125kg just for rider.

Now if you are travelling for a 2 week camping trip..... I did out of curiosity weigh my gear just to see how my panniers work out. 2 x 10kg load, plus top box is allowed 5kg but instead I strap tent on the seat, its 7kg and I leave the top box at home.That leaves me with chair, tables, clothes, cook stuff, sleeping bag, airbed, puddings for 'hosts', notebook computer as I have to keep a work option open,

Take Mr Average rider at 120 kg average and add the 27kg for luggage that's 147kg.

Since we determined a dressed rider adds about 15kg to naked body weight that now leaves 53kg naked weight for the pillion and their gear. For a dressed rider at 130kg, 27kg luggage that's 157kg plus 15kg gear on the pillion now we are at 172kg. That leaves 28kg for pillion with is about the weight of a blow up doll from Utopia or wherever, and the necessary electric pump.

I would hazard a guess that 2 up with luggage something like a 240kg load is more like it. K100RT wet weight is 253kg so that's 493kg. Manual for some models like my K100LT states 480kg max.

I have gone camping with a 110 kg pillion and found that with a good shock the K really enjoyed it.


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1992 K100LT 0193214 101,000 miles
1984 K100RT 0022575 Baja Red bought 36,000 now 84,100 miles
    

15Back to top Go down    shock model on Sat Jul 01, 2017 7:00 pm

scottd

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The shock is a Progressive 1155 250/310. Adjustment collar is at the bottom of the shock, 5 position adjustment is a hex bolt at the very top of the shock. I just put 5 bar (75psi) pressure and took for a ride, did not notice a difference. Open to other ideas - hoping to save the cost of replacing if possible. Thanks again!!

    

16Back to top Go down    Re: rear shock issues - big time on Sat Jul 01, 2017 9:10 pm

RicK G

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The gas pressure in a progressive shock or any shock other than those that use the pressure instead of a spring is not so that you can carry extra load. It is almost pointless using air, the gas should be nitrogen. I know that air is 79% nitrogen but the benefit of 100% nitrogen is required for the shock absorbing to work correctly in any gas pressurized shock. The pressure needs to be at least 20 bar.
I have tried several times to get those progressive shocks to work in even a satisfactory manner and my conclusion is as said before "feed it to a rubbish bin".
There are many very good units available and considering that the abilities of a shock to keep the back wheel in contact with the road is most important then it is of the utmost importance to get a unit that does that well.
The Works performance is a medium range with good performance the Ohlins & WP are the best and also ridiculously expensive, the ICON is a piece of garbage with a weak shaft that will break due to very poor engineering.
There is a heap of small named stuff coming out of China with unknown qualities and HAGON are very stiff and give a harsh ride.
As I said go with a RAM they are a very good unit at a fair price and good back up service.
If you can find a FOX twin clicker and get it rebuilt you will have a good unit but AFAIK they are not available new any longer.


__________________________________________________
If everything seems under control then you aint goin fast enough:- Mario Andretti
Bikes 1986 K100RT, 1993 K1100 LT, 1994 K1100 LT, 1993 K75 RT, 1996 K75RT, 1986 K75 GS, 1979 Z1300 Kawasaki X 2 & 1976 SR 500 Yamaha for now
    

17Back to top Go down    Re: rear shock issues - big time on Sat Jul 01, 2017 11:29 pm

club_c

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Happy Canada Day Scott! How about sliding by a tire shop with a nitrogen tank and having them give you 20 bar of it after you deflate the normal air out of the shock. At least then you'll know if there's any hope. Trust me the guys here know of that which they speak.


__________________________________________________
"There's never enough time to do it right, but there's always time to do it over."

1988 K100RS SE VIN 01477554
    

18Back to top Go down    Re: rear shock issues - big time on Sun Jul 02, 2017 1:25 am

MartinW

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I'm still running an OEM shock, changeover rebuild from RAD Motorcycle Shocky Repairs. They can customize spring rates and damping rates on request. I'm on my second one and happy with it. I just get the standard changeover one with no upgrades. I'm about to clock up 160'000 K's, I think the last one was $250 to $295. I have got the two through the BM shop but next time I will go direct. http://radmotorcycleshockyrepairs.com.au/index.html
Regards Martin.

    

19Back to top Go down    Re: rear shock issues - big time on Sun Jul 02, 2017 1:57 am

Laitch

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I have a Progressive 465 and ride the vast pothole fields that are my town's Class 3 gravel roads. I've got it set so it keeps the wheel in road contact and the bike stays on track. The travel cases have a tough time but they stay attached, mostly. The thing about my Progressive is that it doesn't adapt easily to changing road types and conditions. I've set it so it works best where I want it to work and adapt to it elsewhere. Keep that in mind.

To have half a chance of getting this shock to work for you, you've got to purge the air and replenish the nitrogen like Rick G and club_c are telling you.


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1995 K75T 60,000 miles
    

20Back to top Go down    Re: rear shock issues - big time on Sun Jul 02, 2017 5:45 am

Dai

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Why pure nitrogen? Because it sheds heat faster than an air mix. If you pump air in there the shock will start to fade pretty quickly as it overheats, which is probably why you didn't notice any difference after pumping it up.


__________________________________________________
'83 K100 upgraded to K100RS spec
Others...
'78 Moto Guzzi 850-T3, '79 Moto Guzzi 850-T3 California,'93 Moto Guzzi 1100ie California,
'03 Suzuki Blandit GSF600SK3 (NFS any more because wifey has claimed it)
    

21Back to top Go down    Replacement shocks on Sun Jul 02, 2017 6:49 am

redrockmania

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I agree with Rick G - An Ohlins (purchased used off eBay for approx $500) transformed my suspension/handling and they are readily serviceable. I bought a Works Performance (made in USA - and factory does service on request) on eBay after reading numerous favourable reviews am yet to fit it. I note a favourable comment in this thread about having factory shocks custom overhauled. My brother-in-law has a Suzuki DR650 Suzuki and had his shock revalved and a larger diameter shaft fitted with major improvements in performance. I have White Power (standard fitting) on my Triumph Tiger 800 xcx and am most impressed - KTM use them extensively.

    

22Back to top Go down    Re: rear shock issues - big time on Sun Jul 02, 2017 9:24 am

Point-Seven-five

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My two cents on the Works Performance shocks.

I have two of them. The first was on my K75RT and came on the bike when I got it three years and 28,000 miles ago. Last march I noticed that it had started leaking and had puked out a fair bit of oil. Last May I replaced it with a used Fox Twin Clicker. The bike feels much better in turns and over the crap roads I travel in my 100 mile round trip commute.

The second is on my K75S. It was leaking when I got the bike two years ago and on the 2000 mile trip home had coated most of the rear wheel and final drive with oil. Works rebuilt it for about $100 and for the past 7,000 miles it has worked flawlessly, but not as nice as the Twin Clickers I have on my other two bricks.

In my opinion, the damping adjustments, especially the compression damping adjustment, on the Fox Twin Clicker have made it possible to fine tune the rear suspension on my bikes to optimize the feel of the bike over bad pavement and in turns.

It's a shame they are only available on the used market.

BTW, it is my understanding that Works Performance will rebuild the Fox shocks where Fox won't even supply repair parts. There are other sources of Fox parts and service on the net as well as a downloadable repair manual.


__________________________________________________
Present:
1994 K75RT
1994 K75S
1992 K100RS

Past:
1982 Honda FT500
1979 Honda XR185
1977 Honda XL125
1974 Honda XL125
1972 OSSA Pioneer 250
1968 Kawasaki 175
    

23Back to top Go down    Re: rear shock issues - big time on Mon Jul 03, 2017 7:01 pm

Snod Blatter

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@RicK G wrote:HAGON are very stiff and give a harsh ride.
I can attest to that! Bought a very tired one for 20, looks like it has been in the sea, has weeped a little bit of oil but it's still hard as nails. The rear actually makes a bang over small potholes! And yet if you try and ride in a spirited manner (ahem) it lets the bike wallow all over the place. Very much like their twin shocks - only really good at holding up the rear end.

Still better than the original unit though! Rolling Eyes


__________________________________________________
1989 K100RS SE ABS 8v VIN: 0149214
Others: 1.5 x Honda CBX250RS-E, '94 CB250, '95 TRX850
http://justbikethings.blogspot.co.uk/
    

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