Trying to identify rear damper

[nobackhair]

Last owner ('07) told me rears were Progressive. It must be the springs only because I called them, Prog. and they said the numbers I gave them meant nothing to them. There is a larger no. 1253 above a smaller no. M2232B. Below that, Made in Mexico. I never asked about the springs because there's no I.D. I'm guessing it's about length. I realize this is probably a stretch but I can't find anything to help. I have an idea dampers are stock. They do have an adjustment collar I can adjust by hand. Spring meas. is 9" and damper is 13". I'm sure they are hydralic. They compress somewhat easy w/ no return and they are are a little hard to pull out. Plan on replacing damper w/ Progressives. My bike weighs 420 w/ full tank and I'm 145 soak and wet. I noticed when you call them you have to let the phone ring till it collects dust.

 

[650Skull]

The only way to help is if you post a pic

 

[fredintoon]

Hi nobackhair,
there's two meanings to "Progressive"
The first is the name of a spring manufacturing company and some of their springs are not progressive at all, they are constant rate.
The second is a term describing a coil spring with coils that get closer and closer together along it's length.
As this style of spring compresses the coils begin to touch each other so the spring rate gets progressively higher and higher.
And most of the progressive springs on the market ain't.
Winding a true progressive spring is a costly process.
Most of them are actually dual-rate springs.
Those have ~1/3rd of their coils wound closer together than the rest.
They compress at one rate until the close-wound coils touch each other then they compress at a higher rate.

 

[650Skull]

Fred gave a school lesson on what progressive springs are.


The only way to identify the shocks you have........... is to post a pic.

 

[fredintoon]

Fred gave a school lesson on what progressive springs are.
The only way to identify the shocks you have........... is to post a pic.

Hi Skull,
just trying to be helpful, eh?
And perhaps the OP's PO meant that the shocks had progressively wound springs, not that they were made by Progressive?
Nor do I think a photo would be much help.
Apart from jam-pot Matchie shocks and those that have extra reservoirs they all look just about the same.
Still in helpful mode, perhaps what the OP needs is advice on what shock he'd want as a replacement?

 

[5twins]

The "Made in Mexico" kinda rings a bell. They may be Mulhollands, not a bad aftermarket shock back in the day. I used them on several bikes. Here's some info .....

http://www.thejunkmanadv.com/boge-mulholland-shocks-info.html

http://the520chaincafe.blogspot.com/2014/10/dt1-mx-project_25.html

 

[nobackhair]

I 'm having trouble w/ that at the moment. Sucks.

 

[nobackhair]

I got problem taken care of w/ pic. Sent it to Progressive Susp. and it one of theirs but an older series. They thought I was wrong about the no. 1253. Thought it was a 1283. Still waiting to hear about springs. Sent meas. and weight which is 9" long and 3lbs. for the pair. I was aware of the wound thing. thank you. I inquired just how old. I'm sure their old enough to replace. Probably before gas charged were avail.

 

[nobackhair]

I have some of these on another XS (77). Their noticably different. thx.

 

[5twins]

Yes, they look like a Progressive. The alloy spring preload adjuster rules out the Mulholland. Theirs were chrome steel. The Progressive very much resembles a Koni, in fact looks like a copy, but the Koni will have the actual "Koni" name on it along with "Made in Holland".

The spring weight will be more difficult to figure out. The shock was made to use a spring of a certain length so several in different weights were made, all the same length. Black springs usually had colored paint dots on them for an I.D., not sure about the chrome ones. Even if the chrome ones did have paint dots, they very well could have flaked off by now.

With the springs off, pump the shocks in and out. If you find no "skips" or dead spots in the stroke, then they are probably still good. I would run them. In fact, that's pretty much all I use on my old bikes, old aftermarket shocks. I have mostly Konis, some Mulhollands, and a set of Prolifts. Good new shocks are quite expensive. The $89 sets are mostly junk and a waste of money.

 

[fredintoon]

I got problem taken care of w/ pic.1253. - - - Still waiting to hear about springs. - - - Sent meas.

Hi nobackhair,
the photo shows what's commonly called a progressively wound spring although it's really a dual-rate spring.
What they'll need to determine the spring rate is the wire diameter, the coil diameter and the number of turns.
There's charts available on line if you look so you can too.
Of course, there's two answers for a dual rate spring.
The softer rate when all the coils are working and the harder rate when the close-wound coils are touching each other and only the wider spaced coils are working.

 

[nobackhair]

I only have one to test at the moment but it does have skips. I tried something to fix that that Mike from 650 Central Said to try to get air out by turning damper upside down and pump it a few times. Doesn't help stop the skip. While it was still upside down it did but not when I held it shaft up.

 

[nobackhair]

When you mentioned coil diam. I'm assuming you were refering to I.D.

 

[nobackhair]

Maybe I need to send those meas. to the tech that's helping me. 40mm I.D., 6.8mm rod thickess. The guy I bought bike from refer to the springs that he got them from Progressive. Not that they were Progressive. I can't reach him anymore.

 

[nobackhair]

I went ahead and bought the 12 series. Maybe I'm rushing things but I have spent some real time considering what to get. I originally mentioned My weight and the bike. I've been spending even more time on the front. In my entire life I have never encountered a more varied discussion on anything to do w/ any other part of a bike. So far the closet I've come to making a move to improve, if possible is to drill out the lower holes in rod to 1/4" and drill the top thru w/ the #45 bit. Still I'm skeptical about any of this. I already bought the Progressive brand Springs. Currently I have an 1 1/2 PVC sleeve added and 2" of 15W fork to stock level. I don't care as much about dive as I do about comfort at higher speeds. I'm sure there what I've done could be seriously critisized. Lay it on me! I live in Phx. area and our roads are in better shape than pretty much anywhere, from what I hear. I meet a lot of out of towner that bring that up. Hardly any curves or undulating. But the ones we have I want to be prepared for. I also replaced the bearing w/ the rollers or needles?. Bike wt. 420 lbs.full tank, me: 145
Has anyone ever discuss where we sit on our bike and the effect on how that weight distribution. I noticed at high speed when I move back there is less wobble up front. Seems obvious I guess. Not like I made a revelation.

 

[5twins]

The damper rod drilling you speak of is called the "Minton Mods". Yes, it will help and is a nice basically free mod. It makes the forks much more supple and responsive over the little bumps. Unmodded, you feel all that stuff and the forks mostly only respond to the big bumps. Yes, the PS springs are good. The originals ride nice but are usually too soft, allowing lots of dive when braking. Mod the damper rods, install the PS springs, and use about one ounce more fork oil than speced (7 instead of just under 6). I think you'll like the results. These forks just plain work better with a little more oil and it will also increase the "air spring" effect because there's less air space above the oil level now. This helps reduce the brake dive but doesn't hurt the supple ride over the little bumps.