Help properly using my new Penske

[MajBach]

I recently had an 8983 installed at GP that I need some help with.

It was a busy day when I went to GP to fork over $2000 for a new shock and fork valves. The guy that worked on my bike said to me that he had never done an FJR before and normally worked on dirt bikes. It was also his last day there. After he stated he wasn't sure which adjustment was for rebound and which was for compression, I kind of hinted I'd like someone in the know to come edemacate me. One of the owners came out (Barry maybe) and did spend some time with me but I have to admit, I really didn't retain what he had said; too much too quick. I pretended I understood hoping that the manual they gave me would clarify anything still foggy. It didn't.

I've looked on-line and downloaded every shock manual I could find and still no help. There is no specific 8983 manual and the generic 8900 series that is available on-line and that they provided me is written in a dialect I just don't understand.

Barry demonstrated how to adjust the height and adjust the preload and rebound, and something about softening rebound on colder days I think but the rest I don't recall. There was actually a fair bit of info on the settings and oil they used on my invoice that I wasn't aware of until this morning, such as spring rates and settings set at the factory.

Does anybody know of a good source or thread speaking specifically about this shock?

Some of the things I'd like to understand include:

- the gas pressure valve on the remote canister, should I ever touch it?

- how much pressure should it have?

- does it need to be checked periodically?

- when do you know if you need to add or reduce pressure?

- isn't the compression adjuster supposed to click as you turn it?

- is it normal to have to use a wrench to turn the compression adjuster?

- should I be adjusting preload, compression and rebound to conform to changing riding conditions (like going from solo to 2-up or cool to hot ambient temperatures)?

 

[MCRIDER007]

Don't touch the gas pressure valve...period....unless you are rebuilding the shock. Compression adjustment should have clicks about a half turn apart, you will need a wrench unless you have very strong fingers. Adjusting the preload and damping for changing conditions is a personal preference. I would increase preload for riding 2-up, I rarely change damping for temperature changes since the shock oil temperature is pretty consistent once it's fully warmed up.

 

[El Cajone]

Hey George, a fellow Canuck needs some help!

 

[escapefjrtist]

@Maj - Answers are inserted below:

<<snip>>Some of the things I'd like to understand include:- the gas pressure valve on the remote canister, should I ever touch it? Nope, only if it's being rebuilt.

- how much pressure should it have? Manual says +/- 150psi so that's what I've been putting in after rebuilding.

- does it need to be checked periodically? Nope

- when do you know if you need to add or reduce pressure? Mine started feeling loose and I had to add compression dampening. Also noted more leakage than normal around the shaft. When I tore it apart, the reservoir was at 50 psi.

- isn't the compression adjuster supposed to click as you turn it? More like a detent when you turn it.

- is it normal to have to use a wrench to turn the compression adjuster? Yes, I use a 1/4" drive ratchet, short extension & 1/2" socket.

- should I be adjusting preload, compression and rebound to conform to changing riding conditions (like going from solo to 2-up or cool to hot ambient temperatures)? Preload, yes for extended two-up work to maintain proper ride height. Any other changes, nope.

Record your initial compression and rebound settings so you can always return to original. External adjustments are for "fine tuning" the shock. The internal shim stacks control the bulk of the compression and rebound action.

--G

 

[redneckj]

Post your rebound and compression settings that you have now. Please post your shock setting and your fork settings too. You will need to know how many "clicks out" from "full in" that your suspension is set up now. After that there are plenty of people on here that will help you dial in your new suspension.

Here is my set up:

1.0 springs in the forks

2 1/2 lines showing on the preload

Motul 7.5 weight oil

rebound 7 clicks out

compression 15 clicks out

Penske

850lb spring

Sag set for rider weight and loaded bike

rebound 6 clicks out

compression 10 clicks out

Also, there is a ride height adjustment for the Penske. I have some additional ride height dialed into the shock helping the bike turn in.

I changed from the oil that GP used in my forks to the Motul 7.5 weight. The oil that they used really got thin after the fork oil got up to operating temperature. The thin oil made me have to dial in even more rebound dampening to stop the forks from having a "pogo" effect. By simply changing the oil to the Motul 7.5 weight, that problem went away. The valving is consistent throughout the operating temperature of the fork oil.

 

[MajBach]

Post your rebound and compression settings that you have now. Please post your shock setting and your fork settings too. You will need to know how many "clicks out" from "full in" that your suspension is set up now. After that there are plenty of people on here that will help you dial in your new suspension.

Terrific!

I will post these in a day or two. Not home currently.

 

[MajBach]

Post your rebound and compression settings that you have now. Please post your shock setting and your fork settings too. You will need to know how many "clicks out" from "full in" that your suspension is set up now. After that there are plenty of people on here that will help you dial in your new suspension.
<snip>
Also, there is a ride height adjustment for the Penske. I have some additional ride height dialed into the shock helping the bike turn in.

I changed from the oil that GP used in my forks to the Motul 7.5 weight. The oil that they used really got thin after the fork oil got up to operating temperature. The thin oil made me have to dial in even more rebound dampening to stop the forks from having a "pogo" effect. By simply changing the oil to the Motul 7.5 weight, that problem went away. The valving is consistent throughout the operating temperature of the fork oil.

Okay..

So did some two up riding this weekend and between the two of us, we're probably 450 lbs. I was surprised how planted the bike still felt and how there was no bounce from the extra weight. On the other hand, I really noticed a resistance to turn or lean (is this turn-in?) as compared to when riding solo. I should note I didn't adjust my pre-load for the extra weight.

Another thing I have noticed since having the work done is how much more rigid the bike is when cold. When I leave in the morning, it's pretty cool here, less than 60F for sure, but even when it's warmer, I really notice I have to push to counter-steer while in a turn to keep it leaned as it really wants to stand back up. After 15 minutes of riding, this seems to go away. Kind of fits to what you described before you changed your fork oil. I did not notice this before having the work done. Although, my forks were really soggy back then.

So here are my settings:

Forks

pre-load 3 1/2 showing on .

compression:10 clicks out

rebound: 12 clicks out

(GP set these at 4 'turns in' meaning 2 lines showing, and 12, 12)

36x260x1.05 kg 10.29 N/mm springs

oil height 130 mm, 5 wt oil

Shock

pre-load: see pic below

compression: 9 clicks out

rebound: 16 clicks out

I cannot tell what spring weight they used (not on invoice). I told them to take my weight as 220 (I'm dieting

) , that I ride 2 up less then 10% of the time, but most of my riding is road trips with 100lbs of gear. Invoice states: PENSKE 8983...09 FJR1300 220lbs.

I haven't tried adjusting the pre-load on the shock; not sure how. He showed me a tool - looked like a long allen wrench - and said it came with the shock but it never made it home; must have left it on the bench there.

One final thing: whenever I take my hands of the bars, the bike really leans left. This happened before the upgrade but I noticed it would sometimes disappear completely when I was experimenting with the pre-load and compression settings. Tonight I tried adjusting one of the forks with more pre-load than the other hoping to see if it would maintain a straight up and down but only slight difference. Anyone else ever notice this?

 

[Mr_Canoehead]

You really should take some sag readings. Check this article or do a search. Once the sag is correct, then you can start playing with compression and rebound. If you can't get the sag right with the preload adjusters, you will need to change the springs. I had to back off all the preload on my Penske to get the sag right solo.

Also, my Penske has been on for about 5k km and it was very harsh at first. It has been breaking in and getting more plush as it accumulates some mileage.

 

[MajBach]

You really should take some sag readings. Check this article or do a search. Once the sag is correct, then you can start playing with compression and rebound. If you can't get the sag right with the preload adjusters, you will need to change the springs. I had to back off all the preload on my Penske to get the sag right solo.
Also, my Penske has been on for about 5k km and it was very harsh at first. It has been breaking in and getting more plush as it accumulates some mileage.

Yes that seems to align with my observations as well. Definitely a little more plush than when I first got it.

That article is one I haven't seen before. Will give it a read. Thanks.

Is there a method to adjusting the preload or is it as straightforward as inserting a steel rod and turning?

 

[redneckj]

You really should take some sag readings. Check this article or do a search. Once the sag is correct, then you can start playing with compression and rebound. If you can't get the sag right with the preload adjusters, you will need to change the springs. I had to back off all the preload on my Penske to get the sag right solo.
Also, my Penske has been on for about 5k km and it was very harsh at first. It has been breaking in and getting more plush as it accumulates some mileage.

Yes that seems to align with my observations as well. Definitely a little more plush than when I first got it.

That article is one I haven't seen before. Will give it a read. Thanks.

Is there a method to adjusting the preload or is it as straightforward as inserting a steel rod and turning?

The Penske should have shipped with two small allen head locking screws. 180 degrees out from one another. Loosen one up all the way, take it out and dont put it back in the shock. Loosen the other allen head screw, tighten to increase preload, loosen to decrease preload.

 

[Mr_Canoehead]

Yep, just turn it with any tool that fits in the holes - make sure if you back it off, that it doesn't release all the tension on the spring when the wheel is fully extended - put it on the center stand to check.

Edit: I didn't loosen the Allen screws but the coIlar moved easily. I will check that next time. I would have paid extra for a hydraulic preload collar on the shock if it was offered, but adjusting the Penske by hand isn't too onerous.

 

[rgonanFJR2008]

MajBach

My settings for the 8983 are:

HS Compression 14 (out)

Rebound 18 out

Preload 12mm

Spring rate 800 lbs. ( I am 195 lbs, no gear)

My unit came from Traxxion. Installed locally, by a mechanic who has set up suspension for many riders locally, so I cant really help you with any suggestions on set up. The "manual I received from Penske via Traxxion does not have anything specific for the 8983. On page 35 of 36, it lists the part # "PS-8983" and makes reference to the 8300 shock. Page 6 and 7 in said manual pertains to the 8900 .

If I can be of any further help, please let me know.

Rick

 

[eflyguy]

I am fortunate to have Traxxion in my back yard, and they (well, Lee specifically - now retired) edumacated me on the ways of the force (damping, rebound, sag).. I've upgraded every street bike I've owned with them, and my FJR has their AK20s and a Penske (prior owner).

So here's my point:

I would strongly suggest you go to a qualified suspension expert and have them adjust your bike to suit you. As you didn't buy from them, it's fair to have them charge you, but if you've dropped 2k in upgrades, another $50 in tuning isn't going to matter. Folks pay $200 to have their PC map tuned all the time.

.. and, it will be worth it!

 

[MajBach]

Thanks again for those last few posts. I've now put about 3000 + miles on the upgrades and I'm quite disappointed. I hope I am just doing something wrong.

When I first asked around for advice on upgrading, I wasn't really sure how badly I need new suspension or what kind of difference I would notice. I just slowly began to notice how the bike seemed to dive alot under braking, kind of wallow/bounce while in a turn and it was definitely hard to maintain a smooth arc. After the Penske, I now understood the meaning of the phrase "more planted" from others who had made the switch to high end shocks.

However, in the past several hundred miles, those symptoms have seemed to reappear, except for the fork dive. It almost feels like the old shock. I've looked for leaks and seen none.
At first I thought I was imagining things or perhaps just getting to used to it and more picky. But, someone mentioned earlier that it softens up after a couple thousand miles and maybe thats what's going on here.

Just for shirts and giggles, I tried adjusting the settings to the extremes on either end yesterday. First, I made everything as soft as it would go except for the shock pre-load (haven't touched it yet). I drove for three hours. I did notice a little more of a bounce and also the 'feeling' the back end was loose - as if it would slide out if I leaned more. But this was not abrupt and not violent. There also seemed to be a very willing tendency to roll into a turn which I have never experienced before. Still, I wasn't sure if someone had changed these settings without my knowledge if I would have noticed. Certainly not a stark difference.

Then I went full stiff before leaving the sitting. My fillings practically fell out of my teeth! There was a big difference in the bumps. It was so uncomfortable I almost couldn't continue. On one small section, I accelerated quickly over very small bumps/ridges in the road and could easily feel the bike leave contact with the asphalt. This was actually reassuring to observe for me as I knew the adjustments on the suspension were doing their jobs; this is not something I would have observed pre-upgrade.

On the highway and in the turns I can't say it felt as 'planted' as it did the first few days after the upgrade. The bike resisted turning now as well, rather than wanting to fall into the turn. But, no where near as bad as when cold. Funny, I didn't notice this issue before I had the forks serviced but after, quite noticeable. That is, for the first 15 minutes of driving, I really have to push on the inside bar to get her to lean. Is this the oil viscosity? I think they used 5 weight.

Thursday I leave for a long trip to Calgary-> Glacier NP, Montana and back; should be a good 2000 miles. I'll try the setting posted above and I will definitely try adjusting the preload on the shock. Oh yes, I almost forget...I did do some sag measurements the other day. The total amount of sag was an inch and a half ( just shy of 40 mm). This is centerstand to me on the bike. I think she dropped an 1/2 inch from centerstand to dry weight and another inch with me fat arse. I have a 950 lb spring.

 

[John d]

I think your spring at 950 lb is too much for just yourself on the bike. Try a 850 lb spring. For turn in problems, I would suggest looking at new tires if they are getting worn.

 

[BkerChuck]

I notice your comment that you haven't touched the shock preload yet. FWIW this is generally the first thing you should be setting. It's vital to get that adjustment so that the shock is set for the correct amount of sag for your body weight in riding gear. It's easier if you have a friend who can help. I'm not sure what Penske recommends but I'd imagine that information is available somewhere. Start by setting your sag and put rebound and compression settings close to the middle of their adjustments after you get preload dialed in.

 

[Viper Pilot]

MajBach, Your trying to measure something with a yard stick and cut it with an axe and expecting to call it fine furniture!

Ok, take a deep breath and plan to start from the beginning. First, as has been mentioned before, your 950# rear shock spring may not be the right size. Take some time to obtain your front AND rear SAG measurements. You should have approx 1.5 inches of total rear SAG and approx 1.5 to 2 inches of front SAG with you on the bike and in your riding gear. Make sure you get the stiction out of the measurements by bouncing the suspension a bit before taking your measurements. When taking these measurements also record what preload you are using on both front and rear springs. IF you cannot obtain the correct SAG values you may have incorrect spring rates installed.

After, and only after, setting the correct front and rear SAG, then start the adjustments of the Rebound on first the front and then the rear shocks. Rebound is much more critical then compression. Start with the rebound about 1/3 out from full hard and push down on the front forks and notice how the bike responds. It should rise and settle with just a touch of rebound bounce. BTW, a very good source of how to do this and whats expected can be obtained from on-line videos made by Dave Moss. Check them out.

After you get the front rebound approx. set, go to the rear and follow a similar adjustment and test. Record your values of the front and rear settings for later fine tuning. Now go for a ride over your 'test section of road' and see how it feels. Return to the garage and change only the front rebound 2 clicks tighter or looser and try the static push down test again and note how that looks. Now go for another ride and note the difference. Return and adjust the rebound adjustment 2 clicks in the other direction and redo the push down test and go for another ride and note the feel. Be sure to take good notes and just take your time. After you have a fel for how the front is doing , proceed to the rear shock and start that process again on the rear. Believe me, it takes time and the results will be excellent when both front and rear suspension is balanced with the optimum settings. It's much more sensitive then your thinking and is doable but without the correct SAG (i.e. spring rates) you will just be chasing around a circle and never obtain what you are looking for.

Again, look at Dave Moss's videos and web presentations for more details. Don't be in a hurry and don't give up. Your on the right path, just be patient.

 

[Mr. BR]

I'm in the same boat as I picked up used Penske a few months ago from another forum member.

These details were provided to me:

Penske 8975 (in line double adjustable) with Blue spring at 6 x 850lb setup for 185 pounds rider.

Mileage on the shock is 14,500 miles.

I set the sag initially but I need to recheck it... I'm about 220lbs geared up plus I've got tools/crap in the side cases and my laptop is usually in the Givi top case (I mostly commute).

So you'd think the 850 lb spring might be soft assuming it’s the correct one for the PO at 185lbs? The prev owner must have had it cranked up full stiff as I had to back off the pre-load a bunch just to get close to 1.5" of sag.

I've set the rebound and compression about mid-way but the ride still seems firm.

The Penske is a little longer than the OEM shock so I like the increased ride height which has my pegs (w/lowering brackets) dragging a lot less.. I was about to take those off prior to this purchase.

So, as stated by others, I’ll just be patient and slowly fine tune the shock until I get it where I want it.

Btw, here’s the tool I’m using to rotate the pre-load collar… just something I had laying around that happens to fit perfectly for easy adjustments.

Regards,

Mr. BR

 

[MajBach]

Thanks for this advice. I'll proceed with this over the next week as I'm on a long overdue road trip and report back in. First step is changing the tires; already off the rims.