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Need a special cog/lock ring combination...(19 posts)

Need a special cog/lock ring combination...TFerguson
Nov 17, 2003 12:22 PM
I have a Suzy flip-flop and am using a DA cog and lock ring on the fixed side. The problem is that there are less than 3 threads showing outside the cog for the lock ring. Does any body know of a cog and lock ring where the cog has a recess and the lock ring goes inside to give it more usable threads? Hope the drawing below explains it better.

Thanks,
TF
Which Suzue hub is it?SenorPedro
Nov 17, 2003 1:40 PM
Is it the junior series or a promax?
Basic (cup & cone) (nm)TFerguson
Nov 17, 2003 6:53 PM
re: Need a special cog/lock ring combination...Aussomeman
Nov 17, 2003 1:53 PM
I just bought a Suzue basic rear hub, a Surly lockring, and a DA cog, and I'm having the exact same issue. From the picture of the Surly cog at http://www.bikeman.com/miva/merchant.mv?Screen=PROD&Product_Code=FW2056&Category_Code=COMPCASSTRK , though, it looks like it has the recessed section you're talking about - I'm thinking that should solve our problem. I'm probably gonna order one tonight...

-Steve
The problem with the Surley is...TFerguson
Nov 17, 2003 7:03 PM
that it's chainline is 2mm closer to the centerline. I'm trying to run flip-flop with a SS freewhell and am already 1mm closer to the center line with the DA. How far off can the chainline be before it starts causing problems? Maybe if the Surley has the recessed cog and extra thread on the lock ring, it they will have enough usable thread to put a spacer behind the cog and have a perfect match.

Please report on the Surley when it arrives.

TF
The problem with the Surley is...Aussomeman
Nov 17, 2003 7:21 PM
hmm...i don't know what the chainline will be like as i'm still in the process of building up my bike. are you saying that your freewheel chainline is ok, but your fixed is off? (that's what i assume...)

i'll let you know what the surly looks like in terms of the threading as soon as it comes in, though.

p.s. are you planning on using the freewheel more than the fixed side? just wondering, b/c most people i've heard from who go fixed hardly even use their freewheel, if at all. maybe worry more about your fixed chainline than your free chainline? just a thought.

p.p.s. i'm no expert, so i couldn't tell you how close the chainline needs to be, but i gather that it's pretty important.

-steve
got my Surly cog...Aussomeman
Nov 21, 2003 2:13 PM
just a follow up - i got my Surly cog today and just screwed it on to the hub to check it out. it looks perfect - no lockring threads hanging off, all are engaged.

cheers.

-steve
Does it have the protruding area...TFerguson
Nov 21, 2003 5:08 PM
where the threads go under the cog like the initial picture?

TF
Does it have the protruding area...Aussomeman
Nov 21, 2003 10:03 PM
actually, it doesn't have the protruding area as i thought it might...i guess the cog is just slightly narrower. whatever it is, it looks ok.

i got both the cog and lockring at www.bikeman.com

-steve
Also, where did you get Surly cogs and lockring? (nm)TFerguson
Nov 21, 2003 5:36 PM
1 - 2mm of chainline difference in the rear...victorthewombat
Nov 18, 2003 10:33 AM
is acutally very close. You should be able to build a dishless rear wheel and adjust the balance of the chainline with the bottom bracket and correct chainwheel location. 1mm should not make any difference provided the other tolerances are not extremely close and the frame is a standard 425 - 440mm chainstay.

More of concern is the threads left on the left hand threading on the fixed side...previous damaged as explained below?
The 3mm difference I am talking about...TFerguson
Nov 18, 2003 3:13 PM
is the difference between the fixed cog and the SS freewheel when I flip the wheel. I can't compensate for both, I can only set the chainring between the two. This may well be close enough, I really don't know but am gun shy. See blow-by-blow below.

TF
Probably not a huge dealOverStuffed
Nov 17, 2003 3:08 PM
I've been riding my Suzue Basic with a Shimano (not Dura Ace) cog and Dura Ace lockring since February. It's the same situation, though. Three threads showing for the lockring. I have had zero problems.

--Kevin
Correction: cog is Dura Ace nmOverStuffed
Nov 17, 2003 3:11 PM
I have already ripped it off once....TFerguson
Nov 17, 2003 7:15 PM
I was using it (road conversion) as a track bike this summer. I used the center ring on a triple Tiagra crankset (never do this) on the front. The chain came off the ring and wrapped around the inside spider and locked everything up solid. I skidded maddly for about 8 feet and it then let go. It had spun the cog off the hub taking the reverse threaded lockring with it. The threads didn't even appear damaged. Evidently it just malformed the metal enough, only using those three threads, to just pop it off.
TF
That sounds extraordinaryOverStuffed
Nov 18, 2003 2:02 PM
That's a lot of force, and it probably wasn't in the intended direction. If the chain moved sideways enough (I don't know all the details so feel free to tell me I'm wrong), then it seems that if only three threads are engaged, then it would pop everything off. However, if what's popping the lockring is the force of the cog as it unthreads, then something else was going on. Perhaps the lockring was cross-threaded, or just wasn't tight enough. Either way, when everything's set up right, the chain shouldn't drop like that.

--Kevin
The chain dropped off the inside of the chainring first...TFerguson
Nov 18, 2003 3:08 PM
The track race had just finished and I was heading into turn one and slowing down when the chain dropped off the inside of the chainring. I don't know why this happened. I was using only the middle (ramped) ring on a Tiagra triple crankset. I had checked the chainline by sight, by measuring from center, and with the Park chainline tool. The chain then wrapped itself up in the small spider totally locking up the bike. I skidded for about 8-10ft (they could hear the squealing of the tire in the stands by the start/finish line) and then the rear end let loose and I coasted to a stop. The lock ring and cog were both hanging loose around the axle outside of the threads. Three teeth of the cog were stuck in the chain requiring some effort to pull them out. All my measurements, when compared to data on Sheldon Brown, etc, say everything is 3/32". The chain was standard Ultegra. There was no perceivable damage to the threads on the hub or the lock ring and they were checked by my Mech. Eng. buddy with thread gauges. As I said, the lock ring was only held on by less than 3 threads, but it was on as tight as it could get.

TF
Wow, that sounds kinda fluky...OverStuffed
Nov 18, 2003 6:20 PM
I'm having trouble wrapping my mind around that. The only scenarios I can imagine involve damaged threads or human error. Other than that, it sounds like a one-in-a-million kind of thing. Are you still using the same hub/cog/lockring setup?

--Kevin
Currently rebuilding as a SS/fixed for the street....TFerguson
Nov 19, 2003 9:25 AM
That's why I'm looking for a cog/lock ring that will give me more threads.

TF