Rear Sprocket, Swing Arm axle, and front Sprocket are aligned with new shock?

[Rizzo97]

Just got a new shock and the rear axle, swinger axle and front sprocket are in a perfect line .. Dose that mean that the chain will go loose instead of tight when I sit on it? Can't sit omit because waiting for parts to put back wheel assebaly all back on

 

[my67xr]

yeah, when the swing arm, front sprocket and rear sprockets are all lined up, that is the tightest position for the chain

 

[Rizzo97]

What would be the best way to go about this ? Besides buyin yet another shock, probably about the 6th 7th one I have bought and it's starting to get on my nerve that I can't getone that hasn't got somthing wrong with it haha this one is perfect besides being about20-30mm to short :/

 

[zwebx]

the swinga at its longest distance away you should be able to lift the swinga up and see the back of it (if its arched then the top of it) inline with the engine sprocket.. then that is when its approximately at its longest or furthest away from the engine sprocket and should be your delta chain length

 

[Rizzo97]

Could I lower it 20mm by lowing the preload? Sounds far fetched just typing it haha

 

[my67xr]

increasing the preload won't lengthen the rear shock, it will just make the ride a lot firmer

maybe look at one of these-
Shocker Suspension Extension Dirt Bike ATV Quad Buggy Front Rear Shock Absorber | eBay

 

[Rizzo97]

Would motorbike shops stock them?
i don't really want to wait for one from eBay.
But I will if I have to because it's a good shock, well worth it

 

[my67xr]

some of the pitbike shops might have them in stock ?

 

[Rizzo97]

I mean are they like a well known thing that most bike shops would stock or more of a novilty thing you can only find on eBay? And now that i remember I had a shock the same length in it before but difrent spring rate and my bike went the best it has with it in there but I had to give it t my bro cuz his was bottoming out causing his engine mounts to come loose, anyway, is there any negatives to havin the chain loosen when I sit on my bike instead of tighten? Because I bought the shock thinkingit would be the same as it was with the other one i gave my bro, I just didn't notice they lined up with that shock in there.. When I got the new one I did notice and got a little worried

 

[zwebx]

The issue is, when the swinga is at a lower point, then the distance from the rear sprocket to the countershaft sprocket/front sprocket is reduced therefor meaning the chain will tighten/to the leverage of breaking or serously damaging the engine or the chain.. to the point of cracking cases and bending countershafts and causing carnage.

At the level point the swinger is at its furthest distance from the countershaft sprocket therefor making it the tightest point for the chain to be at and thats what you should adjust for (atleast a decent ammount of slack at that point).

 

[Rizzo97]

So just adjust it differently that normal To suit the swinger angle ? And it should have like 20-30mm slack at this point right? Because I usealy do 25mm when it's on it's side stand (longer shock not the way it is now) so shouldn't it be just off tight at this point so it dosnt come off when the shock compresses and chain goest looser? (in this situation)

 

[zwebx]

So just adjust it differently that normal To suit the swinger angle ? And it should have like 20-30mm slack at this point right? Because I usealy do 25mm when it's on it's side stand (longer shock not the way it is now) so shouldn't it be just off tight at this point so it dosnt come off when the shock compresses and chain goest looser? (in this situation)

Thats a incorrect and unsafe way to do the tension.
Do the chain slack measurement at the tightest point of the chain.
You should also rotate the wheel and chain assembly looking for the tightest point.. (more used on roadbikes)
25mm when theres no sag or weight but how do you know it wont tighten to 0mm when at full extention/level.

 

[Rizzo97]

So whatit should never get close to tight? It should allways have slack? I thought the slack was there because if it was tight when you are sitting on it it wold break over a jump or when the shock compresses? I have tried to do 20-30mm when it's levle/ tightest point but all I got was my chain coming off and braking my stator ..

 

[my67xr]

nah,
it should still have 20mm minimum up and down movement when the front sprocket swingarm and rear sprocket are all lined up

so you need to find a longer rear shock, or add in a shock extender
it might even need a spring loaded tensioner added to the swing arm so it takes up the slack a little

 

[Rizzo97]

Why dose it need to be longer? And cheers il make sure the slacks correct from now on. It's the length I want it to be, if there's any reson it shouldn't be like that thenill change it but it's been good so far, I've been thrashing it.. Gose perfect for me, chain just loosens when it compresses and tightens on decomp/ rebound or whateve,instead of the other way around (with a shock the same length as stock)

 

[Rizzo97]

It's gona tighten and loosen anyway.. Dose it Really matter wich way it tightens and loosens?

 

[my67xr]

ok, but the more the shock compress's the looser the chain will get.

if the swing arm is angled down a bit more than what it is now, then the chain wont slacken as much during it's travel