Knocking rs monarch
 

  You don't need to be an 'investor' to invest in Singletrack: 6 days left: 95% of target - Find out more

[Closed] Knocking rs monarch

28 Posts
12 Users
0 Reactions
157 Views
Posts: 643
Full Member
Topic starter
 

The monarch rct3 on my bike has developed a knock on compression, hardware all seems tight and it only seems to do it in open and pedal. In the firmest "drive" position the knocking seems to stop. Any thoughts oh great hive mind? It's under warranty, but wondering if it's something fixable without sending it away


 
Posted : 26/04/2016 7:32 pm
Posts: 0
Free Member
 

Mine does this too, though it all seems to work fine. Annoyingly mine is out of warranty by about a month. CRC have said i can return it and they will have it looked at but ill have to pay for any repairs. If its under warranty still then just send it off and get it looked at. Wish i had sent mine whilst it was still under warranty!


 
Posted : 26/04/2016 7:58 pm
Posts: 643
Full Member
Topic starter
 

Cheers, seems to work ok but the knocking is very noticeable. I'll look at sending it back


 
Posted : 26/04/2016 8:25 pm
Posts: 0
Free Member
 

Happens to every one i've had. About to send back my third. Spoken to tftuned about it and they've tried to fix ones in the past without success. So get it sent back.

The shock does function ok but the noise will get louder and you'll feel the knock at the top of the stroke as well, which is obviously highly anoying.


 
Posted : 26/04/2016 8:42 pm
Posts: 0
Free Member
 

Mines just gone back as well, tried an air can service first which didn't help.
It's really annoying and as a friend mentioned you need to get it sorted as it may mask other unknown issues


 
Posted : 26/04/2016 8:58 pm
Posts: 21461
Full Member
 

Wife and I both have a notchy feel at about 15-20% sag. Only a few months old. Bit concerned by comments about it being a repeating fault.


 
Posted : 26/04/2016 9:13 pm
Posts: 0
Free Member
 

Happened to the first one on my nomad. Replaced all bearings before realising it was tbe can. 2 year warranty on sram was put to the test! (And passed..)


 
Posted : 26/04/2016 9:25 pm
Posts: 0
Free Member
 

my monarch that came on a recent frame purchace was knocking. returned the shock ti the company and they couldn't repair it. they are swapping it out for a fox ctd shock for me.

not that it matters since I've bought a ccdb inline.


 
Posted : 26/04/2016 9:41 pm
Posts: 0
Free Member
 

All the debonair ones that I've tried, do it.

It's because all things SRAM suck gigantic donkey balls, do yourself a favour and buy fox.


 
Posted : 26/04/2016 10:29 pm
Posts: 643
Full Member
Topic starter
 

Ta muchly all, looks like it'll be going back to CRC later.


 
Posted : 27/04/2016 6:10 am
Posts: 77
Free Member
 

mine is back with fishers with a small but noticeable knock in the first 10-15mm of travel. will see what they say as its a year old


 
Posted : 27/04/2016 7:28 am
Posts: 643
Full Member
Topic starter
 

It seems like a fairly common problem then! Hoping spares are available, I'd rather not have to buy a new shock to tide me over


 
Posted : 27/04/2016 9:15 am
Posts: 1748
Free Member
 

Problem is, if you send it back to SRAM/Fisher. They'll just give you a new one, whichll like have, or develop the same Knock.

I sent mine to Jtec, and he fixed it, plus tuned it to my weight for £40. That was £40 well spent.


 
Posted : 27/04/2016 10:11 am
Posts: 0
Full Member
 

I also had the knock and had it replaced under warranty. With hindsight I should have just had it repaired as warranty can take ages if your shock has to be ordered in from taiwan


 
Posted : 27/04/2016 10:35 am
Posts: 0
Free Member
 

Rickon did Jtec say what the actual problem was?


 
Posted : 27/04/2016 10:37 am
Posts: 21461
Full Member
 

I'd be interested to know exactly what's going on as well.


 
Posted : 27/04/2016 8:19 pm
Posts: 0
Free Member
 

What does this knocking feel like? Mine is brand new done about 30-40 miles and had a kind of 'step' after about 15% of the travel. There's no noise or anything though


 
Posted : 27/04/2016 8:41 pm
Posts: 0
Free Member
 

Sounds like a play in a pivot or worn bushing Neil very distinctive


 
Posted : 27/04/2016 8:46 pm
Posts: 0
Free Member
 

Ah mine doesn't have that


 
Posted : 27/04/2016 9:07 pm
Posts: 21461
Full Member
 

Mine feels like Neil describes. My bushes and bearings are fine but there a "lump" in the travel around 15-20% in.


 
Posted : 27/04/2016 9:28 pm
Posts: 0
Free Member
 

Mine feels like it ramps up type of thing. Bounce up and down and it feels fine with no noise but feels like there's a step at 15-20% mark. See how it goes


 
Posted : 27/04/2016 10:17 pm
Posts: 21461
Full Member
 

That's it. Very non linear with a peak about 15% of travel.


 
Posted : 27/04/2016 11:05 pm
Posts: 0
Free Member
 

I've bought some of the volume adjusters so we'll see how that goes


 
Posted : 28/04/2016 9:52 pm
Posts: 0
Free Member
 

I've bought some of the volume adjusters so we'll see how that goes


 
Posted : 28/04/2016 9:52 pm
Posts: 0
Full Member
 

kind of 'step' after about 15% of the travel

I'm fairly sure this is where the piston slides past the groove in the can that lets air between +ve and -ve chambers. I can't think what the mechanics of feeling it are at this time of night, but I did an air can service when it became very noticeable on mine and it improved it no end

the knock I had was something different though, something loose in the damping


 
Posted : 28/04/2016 10:06 pm
Posts: 21461
Full Member
 

If it was the positive/negative porting, wouldn't it feel less noticeable after cycling past that point a few times?


 
Posted : 29/04/2016 9:08 am
Posts: 0
Full Member
 

Yeah the pressures equalise over a few cycles when you've pumped it up, but I wonder if when the piston is over the port there is a tiny distance where the air is moving between chambers or something and there is a momentary drop in resistance in the shock, giving that little jump feeling.


 
Posted : 29/04/2016 10:39 am
Posts: 21461
Full Member
 

But at the point where the port is open, pressure should be even, tgefire no movement from one side to the other.


 
Posted : 29/04/2016 9:34 pm
Posts: 21461
Full Member
 

Right then, I've done some testing.
Removed the shock from the bike and now can't feel the lump so I'm happy it's not the frame kinematics.

Took the two pieces of air can off the shock, refitted the damper only to the frame and cycled the suspendion. I'm happy it's not caused by the damping circuit.

It must be the air circuit and I did find an o-ring between the positive and negative chamber that looked like it had been pinched. Hopefully that's the cause, air leaking between positive and negative. I hope it's not cause by the designed balancing port between the two. That would really suck if it's a design flaw.

Sounds like someone in Taiwan could have put a few of these together badly.

Don't suppose anyone knows what size these o-rings are do they?


 
Posted : 02/05/2016 7:13 am

6 DAYS LEFT
We are currently at 95% of our target!