Rear Suspension Adjustments

[thane]

Hi. Im brand new to miniriders and need some help setting up my new bike.

Ive purchased a Chinese Torque Dynamic thing with a Lifan 125, which seems like an ok bike so far.

The shock is a spring one without the little can thing hanging off the side.

Id like to make the rear suspension a little stiffer so i dont bottom-out.

What do i do?

From what i can see, i think i need to turn the thingo to tighten up the pressure on the spring, and then lock it with the other turny thingo underneath...

Am i on the right track?? Any help would be a step in the right direction.

Cheers in advance!

 

[fiddy fmx]

im in the same boat as u mate

 

[thane]

Cool. Hopefully we can get some answers!

 

[$heepy]

same with me but i havent had an answer for over a week now so... i dunno

 

[fiddy fmx]

i ride a pitpro 125 rr

 

[pitmaster]

All you need to do is loosen the lock nut with either a C spanner (or hammer and screw driver for the dodgys out there lol)

Than either screw or hammer the adjusting nut down the tighten the spring,

But its not really an adjustment to stop bottening out! its more for adjusting the static height etc,

Cheaps shocks will just bottom out, if its bad you need to upgrade,

 

[unit_mx]

The shock preload collar is the two rings uup the top of the shock. There will be thread on the shock to adjust it up and down. Tightening the collar so that the spring compresses stiffens the shock and the coils are tight. However wont prevent from bottoming out.
The little can thing your refering to is a nitrogen reservoir. Your shock is nitrogen charged meaning you can adjust the stiffness of the shock by adjusting the nitrogen levels stores in the reservoir. There will be a valve underneath the reservoir to which you can connect a pump too or compressor.

 

[thane]

Cool thanks! Cheers for the Technical words too.

My locknut and collar are at the swing arm end of the shock. Should i flip the shock up the other way?

 

[unit_mx]

Yes. If it fits. Alot of shocks are installed back to front.
Having the shock upside down places alot of strain of the shaft and can cause it to snap. Also your shock reservoir is exposed and can easily be snapped off.

 

[thane]

Mine doesnt have the reservior on the outside. Do i still need to flip it upside down?

 

[thane]

This is what i bought, and the setup here is the same as how mine arrived. Minus the gay graphics...

 

[unit_mx]

oh ok
The shock's on these are piece's , get rid of it and buy a fastace, dnm!!
Sorry to dissapoint but there not worth the effort

 

[themountain]

Sorry to dissapoint but there not worth the effort

not necessarely...the shock is a fastace copy , you could refill it with shockfluid 30 w from showa and put 80psi on it ...and NOT WITH A COMPRESSOR..you will blow the seals!!
...besides that spare some money and get a good pitbike ASAP!

 

[thane]

i'll keep it that in mind.

 

[numroe]

The real solution depends on a few things. You'll have to work it out. Some clues ...

Bottoming can be controlled by the compression dampening, the spring rate and the spring pre-load.

Occasional bottoming is not such a bad thing. You should use all your suspension travel at some point on a target track. But bottoming is ideally barely noticeable when it happens. To achieve that you need good compression dampening. Most pitbikes dont have good dampening control (even if adjustable) since it costs too much.

The rear spring (and fork springs) should carry your weight with the right amount of rear (and front) bike height sag when you sit on the bike. The right front/rear height proportions affects the cornering ability of your bike.

If you increase the rear spring preload too much (wind the rear heigher with the lock nuts), then your bike wont have enough static sag (under its own weight without rider) and your rear suspension will "top out" too often and it wont follow the bumps properly either.

If decent handling matters to you, and you have a rear shock without a gas reservoir, then buy yourself a Fastace RC66 or a DNM shock since they are good value and work ok and don't forget they have adjustment options. Then get yourself a rear spring to go on it which (on a mid sized pitbike) gives you about 30mm of static sag and about 70mm of rider sag. Then you'll be in the ballpark.

eg. I weigh 74kg. I use a 800 lb/inch spring with a DNM shock which has had quality oil and gas put into it. I use the above sag figures (approx), and on flat landings with about 1 to 1.5m drop I struggle to feel a bottom out in the rear, and in woops etc the bike handles quite well.

 

[thane]

Awesome. Thanks heaps for that. You make alot of sense. I'll look into another shock for the rear, and some USD's for the front.

I'll also make the adjustments you mentioned to my existing setup in the first instance and see if i get a better feel.. Im yet to actually ride it. Im just trying to set myself up as best i can so i get to enjoy my first days on a track with out spending copius amounts of time with spanners in my hand.

Appreciate your input and time!

Thank you.

 

[numroe]

No probs. The enjoyment gains from better suspension can be so huge. A common statement but so true. Good luck.

Likewise, it's pretty funny to watch people try to ride fast on crappy handling pit bikes. Some are just so bad in terms of suspension and handling geometry.

Keep in mind no point making the shock heaps better but ignoring the forks.

As earlier posters hinted, be real with your bike. It looks pretty cheap. Depending on what you do, if you punish it too much in terms of ground impacts, you might snap the frame and get hurt bad. eg. It could snap in the middle, or the head stem join. More likely it'll just bend badly but you'll ride away from it ok to laugh about it.

 

[thane]

No problems there. I only ride within the limits of the bike, and myself. Ive checked my weld quality and it looks pretty good, considering the cheapness.

I dont plan on going nuts on it. Im 31, and my bones dont bend like they use to!! I mainly bought it for something to tinker with, and to get out and have a bit of fun with a few mates.

 

[pitmaster]

Thane are you a Wakeboarding + PC builder by any chance???????

 

[thane]

Correct! Are you following me!!?