Spree Owners - Assistance PLZ, shock compressed length Q

[burnt_toast]

Asking ANY Spree owners, can you do me a big favor and measure your stock shock length when it is fully compressed? I need the measure from eyehole to eyehole, compressed length.

And if you're a big guy, all the better! The most you can compress it is the number I need. Probably easiest if you sit on the bike forceably and have someone else take the measure.

Help is MUCH appreciated

[Wheelman-111]

Greetings:

I have a Spree shock, but Timmy's been cremated. I'll try to vise it down this evening unless someone beats me to it.

[noiseguy]

I'm betting that shock has 1.5" - 2" compression tops.

[Wheelman-111]

Greetings:

It's probably less than 2 because someplace I read that the total suspension travel is 2", which means the shock itself has less travel than that due to its angled mounting forward of the axle. Beetz, why do you need to know? (Well someone had to ax... )

[scooterwerx]

do you have a ratchet tie down? compress it with that, or just pull the spring off and measure compressed length without spring

[burnt_toast]

I just need to know, and soon if possible. Time will tell wheelman

as far as doing it myself, I don't have time to mess with shock at the moment. Just need to know this info asap

noise 1.5-2in sounds about right, but if anyone else could possibly confirm I would appreciate it very much.

[burnt_toast]

My bad, in last post, I meant I do need the max compressed length

I will just go with 1.75in worth of travel, and account for an error if needed, if nothing else.

[burnt_toast]

just thought of ingenious way to measure max travel..

measure free length, minus: measure of every coil, per coil diam. this way going from free to fully compressed to where coils can go no farther

my eq:
Lfr - (LcoildD*ncoil) = shock travel

L=length, after is notation towards location
n=# of coils present

makes very much sense in my head and allows me to check measure by just a piece of paper and pen, will try it later today yay

[Wheelman-111]

Greetings:

Uh, not trying to burst your bubble Beetz, but the damper may bottom before the coils bind.

I like the ratcheting tie-down idea. Otherwise figure the shock compresses about a half-inch with rider aboard. An inch with Wheelman riding.

[burnt_toast]

Greetings:

Uh, not trying to burst your bubble Beetz, but the damper may bottom before the coils bind.

I like the ratcheting tie-down idea. Otherwise figure the shock compresses about a half-inch with rider aboard. An inch with Wheelman riding.

not bursting it at all.

doesnt matter if damper bottoms out first.

compressed coil length will give me the MAX possible travel length, even if it does happen to be unrealistic and smaller in real life due to damper. statics engineering prevails

and actually I have already done this and fuzzy math calculations kicked *.

MAX stock spree shock travel length of 2.10in

thanks for everyones input!

[noiseguy]

Sounds like you triangulated to an answer that you can use, which is a pretty good way to do it if you don't have the part in hand.

Keep in mind that you'll never want to design a suspension where the limit of travel is the springs completely compressing. If that were to happen, you'd get a vehicle that would "buck" hard under full suspension travel. In the case of a scooter, it would likely throw the rider over the handlebars. On a car it would break something in the suspension. There's some give in the top eye, but not enough to act as an effective jounce.

Jounce is set in different ways; these rear shocks should have an internal jounce bumper (big rubber insert) that comes in at limit of travel. On cars, it's either internal to the strut assembly or external. On full-size trucks, it's that big chunk of rubber that sits between the axle and frame.

I used to run full-jounce tests on some of my vehicles as part of ride evaluations. The test tracks are big chunks of concrete with 1.5' - 3' waves in them.

[scooterwerx]

hey noiseguy, off topic, but have you ever seen the SPC/light racing jounce shock? i know they did a lot of work with GM as far as testing OEM type applications.

[burnt_toast]

Sounds like you triangulated to an answer that you can use, which is a pretty good way to do it if you don't have the part in hand.

Keep in mind that you'll never want to design a suspension where the limit of travel is the springs completely compressing. If that were to happen, you'd get a vehicle that would "buck" hard under full suspension travel. In the case of a scooter, it would likely throw the rider over the handlebars. On a car it would break something in the suspension. There's some give in the top eye, but not enough to act as an effective jounce.

Jounce is set in different ways; these rear shocks should have an internal jounce bumper (big rubber insert) that comes in at limit of travel. On cars, it's either internal to the strut assembly or external. On full-size trucks, it's that big chunk of rubber that sits between the axle and frame.

I used to run full-jounce tests on some of my vehicles as part of ride evaluations. The test tracks are big chunks of concrete with 1.5' - 3' waves in them.

Hmm not sure I follow completely, but get the idea.

I just used the shock travel as a design parameter to keep motor from clearing the custom frame. I added a fudge factor for more clearance as well.

I think the part you're talking about to relate, would be the tongue part on the stock elite motor mount, is that correct? It seems like it makes contact at or before time of full compression of stock shock.

Another thing to note:

This is going on a drag frame which will see LIMITED to NO actual commuting use, so I don't think this jounce deal is something to factor in greatly

[noiseguy]

The coil springs fully compressing would only happen if you took a stock spring and stuffed it over a different damper. Doesn't sound like you're doing that.

I haven't seen that design jounce shock, but GM was looking at one for a 2010 model back in 2005 that I was working on. It was lever-action off the side of the frame, though, b/c we didn't have the room to package one like this.

[burnt_toast]

Just to update for sake of this post (and for WHEELMANizzle) as to the "WHY" I needed to figure this out..

see here
http://www.hondaspree.net/phpBB3/viewto ... 945#p93945