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captainlip
07-08-2011, 08:51 AM
I've never had a problem with shocks but with the big bores I've two small issues

The fronts leak down the shaft a really small amount, how do I stop this from happening?

The rears seem to stick when they are sat fully extended, it's only for the first 5mm of compression after that they are free without any stiff points.
To me it sounds like the piston is catching the bottom of the shock body?

Andyp
07-08-2011, 09:04 AM
On the rear have you checked the shaft is straight? If not it may have a very slight bend maybe , once the bend has passes thro the body it will go free as you say it does .

Have the fronts always leaked ? Maybe time for a rebuild wil new seals .

captainlip
07-08-2011, 09:07 AM
I'll check the shafts!

The fronts always have since new and since a rebuild, it's such a small amount but it builds up, never leaked enough that I've had to top up fluid though

sime46
07-08-2011, 03:05 PM
Try some of northy's whitey seals mate. They may help. Neither of my sets leak at all with kit seals in tho?

paulc
07-08-2011, 03:15 PM
No problems here either with kit seals and abit of green slime

js3
08-12-2011, 10:05 AM
My shocks are leaking from the bottom of the lower shock cap as well.
Not extreme, but you can see a slight film of oil and it starts to build up on the bottom.
I used green slime on the seals. Should I have just used shock oil on the seals?

Maybe there's a better set of o-rings that needs to be used?

thanks

mattr
08-12-2011, 03:43 PM
You have a choice, they either leak slightly and work, or stop leaking and have masses of friction, i think stiction is the term used. You need to make the seals very tight to prevent all leakage, You also increase the risk of nicking a seal during build, which will make them leak a lot.
Your leaky build *probably* has either been built with bottom limit shafts (small outer diameter), or top limit seals (large inner diameter), if its not enough for you to need to top up, i wouldn't worry about it. Just clean the shafts when you get a chance. Or put a sock over the shock to keep the dirt out and the oil in. (stops you getting a paste of oil and dirt worked into your seals.)
(For comparison with your 40 quid a pair shocks, my £800 suspension forks on my MTB leak slowly, but between normal service intervals (12 months) its not enough to cause a problem........in fact all forks leak to a degree. I guess you service/rebuild shocks once a month at least, so no need for concern).

Leak is probably the wrong term TBH........

The sticking at full extension someone mentioned the other day, its likely to be surface tension of the oil "sucking" the piston to the bottom of the chamber, once you get the oil flowing it will go away.

tyreman
08-12-2011, 04:55 PM
I had this with the shocks on my 210 sticking and it turned out that the anodizing was slightly thicker inside the bodies, as a fix on track i reduced the size of the piston, but after speaking to James at durango they sent me a new set of bodies foc.
Great service and back up.

js3
08-12-2011, 09:45 PM
Thanks for the feedback Mattr and Tyreman.
The shocks are really smooth and the oil leak is minimal.
I will keep monitor the shocks more often and keep them clean.

thanks again :)

steveproracing
08-12-2011, 09:54 PM
O rings are porous. I like to leave mine to soak in green slime for 20min or do when they are new. They absorb the slime and consequently swell a little in the process. This makes the seal that much better as it is a little tighter, but due to the fact that the orings are now perfumed with slime u get a lovely free silky smooth shock action!
I swear by this method and my big bore Durango shocks have no leaks with the kit orings. They have very minimal stiction too!!

js3
09-12-2011, 07:18 AM
Thanks Steve :D
The O-ring/Green Slime treatment worked great.
No more leaks :thumbsup:

OneKiwi
09-12-2011, 04:05 PM
Anyone try a 4 hole piston in the BBs?

What will this do?

I presume that Ill have to go lower oils im at 35/40 now so maybe 20/25?

And anyone have a spare shock seal cap? red or plastic

OneKiwi
10-12-2011, 06:44 PM
I built a set today with 4* 1.2 and went with 25 F / 30 R with dark green springs

Little bit cold in the hall and lengthened to the outer position on the rear hub

Car seemed kinda lazy, might try 5wt thinner in both next time.

I ended up going back to my other set
6*1.2 / 40F and 6*1.3 35R with dark green and moving to the 3rd hole in the hub.

Felt a little better but think Ill have to go to the dark blue spring, 1 step harder as it was diving a bit in the corners

Thoughts on this?

steveproracing
11-12-2011, 11:33 AM
both these setups appear very heavily damped and under sprung at the front and oversprung at the rear compared to what most are running indoors

ive had some really good results with:-
front
35wt 6 x 1.2mm dark red springs with 3mm internal spacer + 2mm external

rear
27.5wt 3 x 1.2mm 3 x 1.3mm light red springs




rear springs i seem to adjust track to track between light red, black and dark green

front springs i never change

if u dont want to try drilled pistons in rear try 6 x 1.3mm 30wt

hth

OneKiwi
11-12-2011, 05:39 PM
YOu running the 210?

External spacer so the shaft doesn't go too far into the shock

What track types are you running at? Motor config? Droop?

I give it a run this week

steveproracing
12-12-2011, 04:42 PM
So sorry bud I presumed u were trying them on a 410!!

On the 210. We have been running
4x1.3 ft and 4x1.4 rear with 35/30 wt

Dark blue ft spring light blue rr
2 full turns in on ft droop screw
No internal/external spacers on any shock!!

This works really well on an inddor track with 50/50 mix of carpet and polished floor.

OneKiwi
12-12-2011, 05:18 PM
Doh after I swapped out the pistions last night..
Anyway I might just try iot anyway and change it at the track.

Droop are you meaning 2 turns in from the top or out from the underside.
full rear droop then?

Isn't the rear shock extension a little too much? Why no droop or limiters there?

steveproracing
12-12-2011, 09:12 PM
Screw the droop screw til it just touches the plate then 2 full turns from that point. As for the rear we have not had a need to reduce the droop yet as the car is not transferring too much weight under braking yet!!

The shocks on the 210 have no spacers as droop screws front and rear are easier to adjust on the fly!!

Reducing ft droop is there to calm down the aggressive steering!!