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Haus Boss

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Discussion starter · #1 ·
I installed the Straitline silentguide around 6 weeks ago. And it has been pretty nice to me most of the time, but on occasion while descending, the chain skips around and I could feel the chain grinding a bit, or I couldn't even pedal. Usually spinning the cranks backwards several rotations would fix the problem. So this problem has been getting worse and worse- happened to me 1-2 times during my 2 descents today- and it's a real flow killer! I finally stopped to investigate and what's happening is an extra link is making it's way passed the upper guide- which then becomes trapped by the very guide that's supposed to prevent that from happening! I'm running a 32t specific guide from Straitline on a 1x10 shimano XT dynasis setup (11-36 rear cassette).

Do I need to rotate the guides X amount of degrees CW or CCW? I'm really getting sick of this and I hope the next tweek will solve my drivetrain problems.

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I had that happen initally with the same 32T specific guide on my Reign-X.

When the rear would compress, sometimes enough chain slack would somehow build up and pop out as you describe.

Rotated the whole thing CCW , just until the upper guide bits barely kissed the chain with the rear end fully compressed -deflated the shock to check that- and so far, it's been fine. Try it and see - if it doesn't work, loosen it up and try the other direction I suppose.
 
No experience with it but I'd say Scrubs got some good advice and worth giving a try. Also Sneek could be right about your chain length. let all the air out of your shock and fully compress the suspension, in this position with the bike in big/big the RD should be roughly @ between 4-5 on a clock face, if it's more like between 5-6 then your chain's too long.
 
Discussion starter · #7 ·
I lost 2 links recently due to a broken chain about 3 weeks ago- and I think this chain guide problem is what caused this. It's not a chain length problem- after losing those link I'm pretty much at the point where removing additional links would overly stress the chain. I'll be making some adjustments rotating the boomerang on the ISCG tabs as Scrub recommended- I'm hitting some really rough n nasty stuff after work so we'll see how the adjustments workout. I have a feeling a few mm of rotation will fix the problem.
 
Trust me when I say this guide stand's up to any rough n nastyness you throw at it. I've been running mine on my Scythe for 2 years now and have 0 issues, set and forget, no skipping or jamming chains like you're experiencing. Isn't your chainring worn out causing chainsuck by any chance?

Can you get a good picture of the front/ rear head on so we can see the clearance? One possibility is that you've spaced it too tight, the crank/ back plate could flex causing the chain to do all sorts of funny things.

Just springs to mind, is this happening in any particular gear or allways on high/ lowest? Then you might have a chainline issue.
 
Discussion starter · #10 ·
I ended up riding with my buddy who also has a Rune but he has a 32-36t Straitline guide on his bike. Before the ride I completely maxed out the boomerang in the CCW direction- you can see from my pix above I only had a few mm to work with in this direction. Our first run was down a technical and rutted out fall line trail- no snags on the chain there. My second run was down the legendary Repack Road in Marin County. This fire road has some fairly large water bars at speed and some high speed chatter- what seems like the optimum conditions to cause the chain problems I was having before. Good news is the chain didn't skip. I did have one hard landing coming off a water bar around 25mph and I was trying to pedal as soon the the wheels touched down but the chain + cranks completely froze for a 1/4 second or so. The cranks/drivetrain immediately unfroze as soon as the rear suspension rebounded from the hit. I had this occur previously on another trail and it can be a bit scary because it completely threw off weight forward and I damn near bucked myself over the bars.

My buddy says he experiences the same issue on his rune when taking a big hit (Drivetrain/cranks completely freeze while the rear suspension is towards the end of its travel)- Anyone else have this problem? I may try rotating the boomerang the CW to see if I can get this thing completely dialed in.

In regards to drivetrain issues- that's definitely not the problem. Derailleur is properly tensioned, cogs/chainring aren't worn down, and my freehub is running like a 240s should- flawless!
 
Discussion starter · #12 ·
Figured I should clear this up. After rotating the boomerang CW in line with the propery position straitline recommend- the problem disappeared. Much happier now that I can spin my cranks without the drivetrain jamming!
 
Any more trouble Haus? I've got the same issue except it's happening multiple times per ride and I have to pull the crank to fix it. Big PITA.
I tried rotating CW like you did but it didn't do anything. Chainline, chain length, ring wear, are all fine.
At this point the guide is useless out of the box. I emailed Straitline but they're 'checking with the tech department'.

I'm pretty sure that somehow the chain is jumping over the top teeth of the ring, not sure how but putting a couple zip ties around the top slider to decrease the gap between the slider and chain seems to help. The mechanics of it don't make a lot of sense though.
 
Same problem here, tried changing chainring and rotate the boomerang, no luck..
Thought the chain maybe was stretched, so put a new one on yesterday, hoping it will be fine now - fingers crossed..
Exactly. I usually only get one or two links bunched, that's quite a few. Let's keep this updated if we figure anything out. I'm trying a new ring today. Next I'll try a different chain.
Last resort will be to add to the top slider, closing the gap above the chain. What to add I don't know, maybe just a pan head screw into the slider over the chain.
 
Did you people try to remove the lower slider?

It seems, from my armchair here, that the chain gets jammed between the lower slider and the chainring ( somehow ) and while you pedal it gets slacked off because it is jammed at the bottom.

Alternatively - fully compress the suspension while the guide is on and see if the chain can freely ( no bends whatsoever ) mesh with the chainring on the upper part of the drivetrain.
 
I think I got it. Put on a new Surly stainless steel 32t SS ring to replace my Salsa alloy SS ring. No jams! So far so good...The Surly teeth are a hair taller, I was doubtful when I lined them up and saw how small a difference it was.
I also had added the provided spacers, the chain almost touches at each end of the cassette now, but still clears the bash and slider side-wall.
I'll update if it happens again, still pretty sure it's the top slider because it has a larger gap so the chain can bounce through.
 
Any experiences running Silentguide on Rune V2? I have 35t chainring and 34-36 Silentguide and it has to be almost fully CCW to even fit the frame. So it's no where near how it should be according the Straitline's instruction.

Bike is not fully assembled so haven't tested it yet. Wondering should I get something else instead of Silentguide that fits better. But seems like this new Rune is not the easiest frame to properly fit chainguide...
 
yes it's a Renthal, but had the same issues when I swapped it for a Chromag:-(

Never had this problem on my old rig, and the only difference between those two setups is the rear mech.
(old rig = saint medium cage mech, new rig = saint short cage mech)
could lack of pressure on the chain, from the shorter cage, be the problem??
 
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