Shock recommendations, please

[mikesim]

My '78 XSE is completely stock and I want to keep as stock as practicable. The suspension is like riding on a spring/sprung rocking horse. Any damping in the shocks or forks is forever gone. What shocks do y'all recommend and what about rebuilding the forks? In reviewing the many posts in the forum I gather that y'all don't think to much of the shocks from Mike's. Where, then, is a good source or OE equivalent suspension components?

Many Thanks!

Mike

 

[grizld1]

The only way you can lose damping in your forks would be incorrect fork oil (too thin) or no/low fork oil. 10W Spectro fork oil and maybe new seals should take care of that. If springs are sacked, Progressive Suspension makes a replacement. The best deals I know of for decent shocks are from Progressive and Hagon; with springs you'll wind up paying around $200 per pair. OE unladen shock length on your bike is 12.75" eye center to eye center. Taller shocks improve handling significantly; consider 13-1/4" or 13-1/2" eye-to-eye length. Call Michael Morse at 650 Central.

 

[mikesim]

Thanks Griz, I will look into those shocks. I plan on draining and refilling the fork oil next weekend.

Mike

 

[5twins]

That should help a lot. The fork oil is probably shot or low, or both. Use slightly more than the spec of just under 6 ounces. Try 6.5 to 7 per leg. These forks just plain work better with a little more oil in them. The resulting higher oil level in the tubes provides more of an air spring effect and that greatly reduces the dive during braking. You can also add 1" preload spacers to the springs to stiffen them up some. They are a nice dual rate spring, just too soft, even with the adjustable caps set at their stiffest. You've got a week so you may also want to research the Minton Mods for the damper rods. Griz isn't crazy about them but I like them and think they help, and they're basically free to do.

 

[grizld1]

I have no problem with Joe Minton's idea of quickening the damping action a bit in the overdamped front fork and stiffening the too soft springs a tad. It will help. But emulator valves are a whole different ballgame; they enable damping that varies with different surface irregularities to keep the rubber hooked up with the road, and do very well what dual rate springs do rather poorly. Really, what you do for forks and shocks depends on what you want out of the bike. My issue with Minton is that he gave too much bad advice. 5twins had to correct Minton's spec on damper rod hole enlargement. I had to find out the hard way that no, Joe, OE valve springs will not hold up to use with a Shell #1 cam, and no, Joe, the limiting tabs on the ignition advance governor will not hold up to being tapped or bent to correct the advance curve. Folks say "Well, you can forgive that, he wasn't an XS650 specialist." I don't buy that. If you don't know the facts you can either consult folks who do, or you can write as if you know the facts. The first course of action is known as research. The other course is called bluffing (when the situation demands polite usage).

 

[grizld1]

Mike, one more thing (you may be aware of this, but others may not). True, there' s a drain screw at the bottom of each slider, but it's a good idea to remove the forks from the clamps so that you can flush them thoroughly with solvent (I like diesel fuel for this). You may be shocked at the amount of swarf that comes out. Mating surfaces between tube and slider should be kept in alignment. To do this, paint mark each tube at the split in the upper clamp.

 

[mikesim]

Thanks once again for the info. I will look at ordering new shocks soon. I was also considering flushing out the forks with kerosene after draining, but I was going to do a quick and dirty job and drain the old fluid, refill with kerosene and work the forks up and down, drain and refill several times while the forks are still in place. The refill with fresh oil. During the winter I will then remove the forks, clean and rebuild them properly. Anyone see anything wrong with my kerosene flush in situ?

Mike

 

[grizld1]

The main problem is that the drain holes are very small and are not located at the bottom of the sliders (they can't be, of course). You won't be able to remove the kerosene, diesel fuel, etc.as thoroughly as you would if you inverted the forks to drain. If you want to do a fast temporary flush and fill, consider flushing with fork oil. If you find that little or nothing in the way of fork oil drains out, you'll need new seals.

 

[gggGary]

The main problem is that the drain holes are very small and are not located at the bottom of the sliders (they can't be, of course). You won't be able to remove the kerosene, diesel fuel, etc.as thoroughly as you would if you inverted the forks to drain. If you want to do a fast temporary flush and fill, consider flushing with fork oil. If you find that little or nothing in the way of fork oil drains out, you'll need new seals.

AND new brake pads..............

 

[mikesim]

I'm getting ready to pull the trigger on some Progressive 13" shocks from 650 Central. I am puzzled at spring rates though. I am about 160# and will very, very rarely have a pillion or be laden in any fashion. I am not interested in peak performance handling at all. Based upon that, what spring rate would be good for my situation? Also, what is involved in installing the springs on the new shocks as they do not come preassembled?

 

[5twins]

If you ask 3M when ordering, I'm sure he can recommend the proper spring rate needed for your weight. He can probably mount the springs for you too. To install the springs yourself, you would need some sort of spring compressing tool. There are homemade ones detailed here on the site. Doing a search would probably turn up the posts.

 

[grizld1]

Yep, Michael mounts the springs on the shocks that he sells, you don't even have to ask! Just tell him what model you have (weight varies from year to year) and your weight.

 

[mikesim]

Thanks for the advice. I pulled the trigger and MMM is shipping me two new shocks. He recommended ones that are one inch longer which he indicated improves handling. Anything will be better than the OE pogo stick shocks that are on the Yammy now. Being that they are one inch longer, any installation pitfalls I should be aware of or sidestand or centerstand issues? I'm assuming (yeah, yeah, I know!) that its just a simple unbolt off rebolt on process like other bikes I have serviced.

Mike

 

[grizld1]

If you ordered Progressive Series 14 oil damped shocks, they'll be a bolt-on fit. If you ordered Series 12 gas damped shocks, you'll need to modify the chain guard to get the bottom of the left shock to clear. Be very sure that steering head bearings and swingarm bushings are in top condition. Raising the rear a full inch will give you steering that's faster and more linear, but it will also aggravate the effects of any existing chassis and suspension defects. The only effect re. the center stand is that you'll find it much easier to pop the bike up onto it. The bike will lean more on the side stand. 5twins wrote a post showing a side stand modified to compensate by adding material to the foot; a search should turn it up, or maybe he'll be kind and post a link.

 

[mikesim]

Thanks for the reply. I got the 14's so it should be a piece of cake (famous last words!)

Mike

 

[5twins]

With 1" longer shocks, the sidestand will most likely be too short now. The bike will lean over too much. You can carry a little block of wood around in your back pocket to prop it up or you can fix it permanently by welding some plate to the bottom of the foot. It usually requires 1/2" to 3/4" of plate thickness to do the trick. I test park the bike on some pieces of plate to find out just what I need.

 

[mcjongs]

Hi Guys.

I Need new shocks as the ones that was on the bike when I bought it two years ago are crapp! (some universal stumpy shit )
I searced the forum and found this tread to be the most recent re. rear shocks..
My question is wether I can use 350mm YSS shocks like these or if they are too long/hard on damping and spring rate? : https://www.ebay.com/itm/283351319331?ul_noapp=true
I have used similar piggy back YSS on a 1980 Maico 440 and they performed really good.

Jon

 

[motormike]

Had excellent results with Hagon's.. not cheap..but they work. Got then on 3 of my bikes.

 

[arcticXS]

Hi Guys.

I Need new shocks as the ones that was on the bike when I bought it two years ago are crapp! (some universal stumpy shit )
I searced the forum and found this tread to be the most recent re. rear shocks..
My question is wether I can use 350mm YSS shocks like these or if they are too long/hard on damping and spring rate? : https://www.ebay.com/itm/283351319331?ul_noapp=true
I have used similar piggy back YSS on a 1980 Maico 440 and they performed really good.

Jon

Hi! Good to see a fellow Norwegian on the forum! 350 mm long shocks may be too long, and cause chain rub on the top of the swing arm. Grizld recommended 335 to 340 mm length in a post in this thread. I believe that is very close to max. length. Spring rates and damping are very much depending on bike and rider weight, riding style, and swingarm/frame/ shock mount geometry. So it os hard to give any advise. Race Tech in the US will build shocks according to your requirements, and Falcon Shocks in the UK as well. Race Tech will ask for a shock geometry data, as well as weight info.
I do have a set of Hagon's for XS650 somewhere in my stash. Bought new in 2010 or 11, only used 1 summer. (Then I bought a pair of slightly longer Ohlins) I am happy to sell you those, if you want. Right now I am abroad, but will be home in a weeks time.

 

[grizld1]

Race Tech and Falcon are fine recommendations if you want high performance and have deep pockets. 350 mm.=13.77 in, which is 1.02" taller than stock (~12.75 in.) That should work fine. YSS shocks are OK, but that price is low enough that you might want to ask a few questions. Re. spring rate, can't tell anything from the photo and don't know weights for you and your bike. But if the shocks are legit, you'll be saving enough to change springs and still have a decent deal.