Shocks

[SCook]

I am wanting to put some new shocks on my XJ1100. I was wondering what brands / size etc that anyone has found to work well on an XJ. I ride primarily one up but sometimes the wife is on with me. Any suggestions?

SCook
Fayetteville, AR

[TopCatGr58]

Hey there Steve,

Welcome to the FORUM. This forum has a nice search feature at the bottom of the page. If you do one for "shocks", you'll then find a few threads discussing them. IIRC, the XJ had air adjustable, and they are linked. You can spend from under $100 at JCW and others, to several hundred. The links section I think lists places where parts are found, like Partsnmore and Dennis Kirk and such.

I'm running the cheap JCW ones on my 81XS, I rarely ride 2 up, but when I do, just have to change the preload,and they seem to work well enough for me. Good luck with the search.
T.C.

[Jerry]

Do a search for 'shocks' and you will see several posts on this topic. You can use stock length shocks (12.5 inches eye-to-eye) go shorter to lower the bike (down to 11.5 inchers) or longer for more suspension travel (up to 13.5 inchers.) Some come with new springs, some are shocks only and you need to re-use your original springs. Originals are not bad, by the way, but if you go after-market you can also get springs that have different load characteristics (rate) than originals, which are dual-rate.

Progressive shocks are popular, but several brands are available. Be aware that the XS/XJ shocks use a different lower mount on each rear shock, but most shocks come with adapters (inserts) that make putting on new shocks fairly straight forward.

In the Progressive brand, look at the 412/12 series or the 418/18 series. Part numbers are 418-1007 B/C, 18-1005, 412-4207C, or 12-1201B. (B = Black, C = Chrome.) Differences are in type and number of external adjustments. The 418 series sells for around $435.00 per set, and are top of the line from Progressive. The other models are less expensive.

Again, if you prefer a 13 inch shock instead of the OEM 12.5 inch shocks, Progressive recommends getting the 418-1026B/C or 412-4212C shocks for your bike. A 13 inch shock will allow you to use a lower preload, giving a ride that soaks up smaller bumps better. All units listed come with new springs. You can get the shocks without springs as well.

Many less expensive units are out there and are noted in previous posts.

[MartyA]

Can I get some opinions on shocks? Apparently there are differences in the standard 12 1/2" shocks. I had a used set that I picked up a a flea market for $10 a few years ago. They worked fine, until SWMBO started riding along last year. We would bottom out on occasion - she is only an additional 125 lb, but apparently enough extra weight to cause this. They were obviously worn out. So near the end of the summer I bought a cheap set from JC Whipme, just to get through the rest of the summer. With these new shocks, the bike is lower and with my wife on board I have to tip the bike way over to the right to get the kickstand down. Even alone on the bike I am riding much lower, still have to lean the bike over to the right to get the kickstand down. Scraped the muffler pretty good in Georgia because of this. Almost impossible to get the thing onto the center stand. With the old shocks this was not the case at all. I could get the kickstad down no problem, and the bike stood higher. Both shocks measure 12 1/2" eye to eye. So what's the difference? I had both sets of shocks set at the firmest settings.

I am planning to purchase new shocks, but how do I select the correct ones? Given that both sets of shocks are the same length, why do I ride an inch or so lower with these new cheap ones? And what do I order to get back up to where the old shocks were? Parts n More sells XJ shocks that are 13 1/2", is that what I need?

If it is the spring rating that made the difference, how do I order what I need? Most of the sites that sell shocks do not list the spring rates, just lenghts, and those that do I don't understand the numbering anyway.

Anyone have any ideas?

[Jerry]

spring rates

Coil springs, like those used in motorcycle front forks and on shock absorbers, are rated by the weight it takes to compress them. Generally, single-rate springs take the same amount of weight to compress them each inch: say 100 pounds to compress them 1 inch, 200 pounds to compress them 2 inches, and so on. Coils of the springs are uniform distance apart from spring end to spring end.

Dual-rate springs of the type used on the XS/XJ rear shocks are a bit different. Coils are not uniformly spaced; they will be farther apart on one ond of the spring and closer on the other. While it may take 100 pounds to compress them 1 inch, it may take 220 pounds to compress them the 2nd inch. This makes them 'softer' and more supple for small bumps, but keeps the shock from bottoming out on really heavy loads or large bumps.

Progressive fork springs (the style, not brand) are similar, taking more force to compress them the 2nd, 3rd, and subsequent inches. Supple for small bumps, stiff under heavier loads. Stock fork springs are not progessive.

One note for air adjustable suspensions, like the XJ: adding air only changes the amount of initial force required to get the suspension to move, it does not change the spring rate.

It can be hard to find the data on spring rates. Progressive seems to be best about this, as I have seen the specs in Dennis Kirk catalog and on the Progressive web page. Stock values for the XS/XJ are 120/160 where the first number is the force required to compress the spring 2.2 inches, and the second number is the force required to compress the spring after the first 2.2 inches of compression.

If you run heavier loads or carry a passenger, you might look into springs with higher ratings.

Hope this breif explanatio helps.

[MartyA]

Great info Jerry. You should add this stuff to the Tips section, "Making sense of Shocks" or something. Thanks. I understand a lot more now, looking at the listings when I am shopping around. By the way, I found this on the Progressive Suspension website chart for XS1100 78-81:

http://www.progressivesuspension.com...AppsNumber=507

I guess I need 'heavy duty' since I am way above the Progressive recommendations for 'standard.'

So I have been wading through the info here, at the Motorcycle Accessory Warehouse web site:
http://www.accwhse.com/progress.htm#Shocks

and now it makes sense.

I can buy the 140/190 springs for $59, a set of 12.5" (heck, why not 13") Series 12's for $141, that's $200. Not bad. And this way I know I am getting 'heavy duty' springs. Might just order them today.

I have never bought shocks and springs separately, do they go together OK?

Thanks again Jerry, you are a wealth of information.

[Mike Hart]

Marty, I put the heavy duty springs on the Progressive shocks on my XJ.

At the time, I weighed in at 245, and the springs were waaaay too stiff with minimum preload. Every pavement crack jarred my kidneys. With a passenger of 150+ or a lot of camping gear they were just about right, but still with no preload.

However, the 'regular' weight might be too light. DennyZ put stock XS springs on progressive shocks and said they were inbetween, and worked fine.

Maybe longer than stock shocks can take the heavy duty spring. If I were doing it again, I'd try the XS springs first, and if they were too light, then go to the heavy duty.

You need some kind of press arrangement to get the springs on the shocks, it isn't something you can do by hand, and a compressed spring can launch pretty dramatically

[MartyA]

Hi Mike!
Yeah, I am worried about going too far the other way. That list is what Progressive suggests, I guess I have to trust them. Thanks to Jerry I understand the list of spring rates, and there are some stiffer springs, and some less stiff ones listed. Not knowing what I have had makes it a bit of a guess trying to upgrade. I was aware that I was taking a chance going cheap last fall and it might not be the best thing to do, but I needed something to get through the end of the year. The JCWhipme shocks only list length. Looking at the Parts n More site, the photo there looks exactly like the JCWhipme photo, and also only lists length. I guess I will stay away from them. Don't get me wrong, the JCWhipme shocks are just fine for riding down the highway, even two up. Never bottomed out, even with the wife aboard. The challenge is the curves - remember my muffler and N. GA? - and the kickstand, due to the much lower ride height. On the kickstand the bike barely leans at all. Shooting sparks from the pegs, center stand, kickstand, and muffler on gentle curves gets annoying.

I mis-listed those springs - Progressive suggests the 120/170 as the 'heavy duty' for a bike with a rider over 200 lb and / or having a rider more than 50% of the time, and the 105/150 as the 'standard'. Hey, if I'm wrong I'll put up with it for a while and the try again. Now I need to find a spring compressor...

You do have a good thought there. Longer shocks with regular springs. Do those shocks all have the same eyelets for mounting? If I order those 13.5" XJ shocks from Parts n More, will they fit my XS mounting bolts? This might be a good sheap 2nd trial. And then I won't need a spring compressor...

[jetmechmarty]

Dennis Kirk has the tools you need. Have a look here: http://www.denniskirk.com/jsp/produc...eafCatId=41810

[MartyA]

Marty to Marty-
Kewl! Thanks!