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RADBMX.CO.UK  |  Technical & Reference Section  |  Tech and Restoration  |  Bit of a tight spot (in chain)
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Author Topic: Bit of a tight spot (in chain)  (Read 2137 times)

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sweetbeats

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Bit of a tight spot (in chain)
« on: October 30, 2008, 01:43 PM »
Alright,

Fitted a new izumi chain last week and have noticed that in one part of the chain it is fine but if i turn my cranks half a turn it is tight as anything!
Is this just down to being new or is it a piece of jap crap any ideas? :daumenhoch:

subversion

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Re: Bit of a tight spot (in chain)
« Reply #1 on: October 30, 2008, 02:02 PM »
Can you put a pic of the complete drivetrain up dude?

 :daumenhoch:

sweetbeats

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Re: Bit of a tight spot (in chain)
« Reply #2 on: October 30, 2008, 02:04 PM »
What bits that?


Offline harris

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Re: Bit of a tight spot (in chain)
« Reply #3 on: October 30, 2008, 02:06 PM »
somethings not quite inline
could be back wheel not sat square or   probably on the cranks area  as in chainring  

Offline phantom photon

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Re: Bit of a tight spot (in chain)
« Reply #4 on: October 30, 2008, 02:06 PM »
Is it a left handed or right handed chain you're using?

Offline LucyLastic

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Re: Bit of a tight spot (in chain)
« Reply #5 on: October 30, 2008, 02:07 PM »
This is caused by a warped chainring, I believe (but could be wrong).  I think you can get rid of the problem by putting spacers/washers on some of the bolts.

Please correct me if I'm wrong but I have the same problem on my Haro.

Offline Bob_Acid

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Re: Bit of a tight spot (in chain)
« Reply #6 on: October 30, 2008, 02:11 PM »
Does it have a spider/chain ring set up?

sweetbeats

  • Guest
Re: Bit of a tight spot (in chain)
« Reply #7 on: October 30, 2008, 02:49 PM »
This is the set up,dont think it is the chainring as it was brand new and the powedisc is minty too...checked wheel and looks pretty square...do you think the problem will ride out..I only built this last week and already i am thinking of selling it...it is just making me angrier and angrier :D even looking at this picture i want to smash it up :4_17_5:



any old freekin iron!
« Last Edit: October 30, 2008, 02:53 PM by sweetbeats »

subversion

  • Guest
Re: Bit of a tight spot (in chain)
« Reply #8 on: October 30, 2008, 02:55 PM »
More than likely the chainring & spider on the crank slightly off centre. you can mess about with it to improve things by loosening off the chainwheel bolts & retightening them (without the chain on) & also loosen & retighten the spider on the cranks. Also watch your freewheel whilst cranking the pedals backwards & forwards, is there any 'wobble' in the freewheel at all?

Offline LucyLastic

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Re: Bit of a tight spot (in chain)
« Reply #9 on: October 30, 2008, 02:55 PM »
I have the exact same mirage disk and sugino chain ring, one of them will definitely be warped slightly, a washer should fix it.  Am I right, Bob?

sweetbeats

  • Guest
Re: Bit of a tight spot (in chain)
« Reply #10 on: October 30, 2008, 02:57 PM »
I will have a look after my tea...it really is starting to drive me nutz this bike..been getting on my ti@s since I started it :LolLolLolLol:
« Last Edit: October 30, 2008, 02:59 PM by sweetbeats »

sweetbeats

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Re: Bit of a tight spot (in chain)
« Reply #11 on: October 30, 2008, 02:58 PM »
More than likely the chainring & spider on the crank slightly off centre. you can mess about with it to improve things by loosening off the chainwheel bolts & retightening them (without the chain on) & also loosen & retighten the spider on the cranks. Also watch your freewheel whilst cranking the pedals backwards & forwards, is there any 'wobble' in the freewheel at all?

Checked freewheel no movement at all :daumenhoch:

Hi lucy where would i put the washer?
« Last Edit: October 30, 2008, 03:01 PM by sweetbeats »

moley

  • Guest
Re: Bit of a tight spot (in chain)
« Reply #12 on: October 30, 2008, 03:19 PM »
Are you using a reducer/top hat so that the spider fits the spindle?

If you are, was there any play when the spider, top hat and spindle are assembled (before you tighten up)?

If there is then the spider might be slightly off centre!!



Also try loosening off the Chainwheel bolt on your crank arm.  Just to check whether tightening the chainwheel bolt has caused the spider to pull out of alignment.  If it is then you might need a washer between the crank arm and spider where the chainwheel bolt goes through to take up the slack so that when you tighten it it doesn't warp the spider.

If your spider is warped where chainring bolt is attached then it would cause tightening in that area!!

When the Chainring bolt area is off the chain (between the top and bottom of the chain) then it will feel loose!!

And tight when the chainring bolt area is furthest from the Freewheel!!

sweetbeats

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Re: Bit of a tight spot (in chain)
« Reply #13 on: October 30, 2008, 03:23 PM »
Cheers Fella I will have a muck about with the bolts shortly and see what happens :daumenhoch:

GREMLIN

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Re: Bit of a tight spot (in chain)
« Reply #14 on: October 30, 2008, 03:30 PM »
When I've had issues like this before I always start with checking the run of the chainring.
I start by removing the chain.
I then use a pen/pencil and hold across the chainstays with the tip next to the edge of the chainring teeth.
Then I turn the cranks and see for sure if there's wobble, or back to front movement showing it's off-center on the spindle.
It doesn't have to be too far out for it to create major slack/tight rotations.

Then I'll put a long straight edge along the chainring and back to the freewheel to see if that's out.

On a couple of builds where I've had this problem I put the chain back on the bike.
Then turn the crank so it's at it's most tight, then undo the chainring bolts.
I then pinch the two sides of chain together and tighten a couple of the bolts.
Spin the cranks a couple of times and see if it's loosened a little.
9 times out of 10 with a bit within 2 or 3 attempts the problem is sooo much better.

Just my tuppence worth   :daumenhoch:   G.

sweetbeats

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Re: Bit of a tight spot (in chain)
« Reply #15 on: October 30, 2008, 03:35 PM »
Cheers Gremlin Ill have a tweek later on see if I can sort it :daumenhoch:

moley

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Re: Bit of a tight spot (in chain)
« Reply #16 on: October 30, 2008, 03:41 PM »
Dont remove the chainring/spider bolt.  Just fully loosen it!!

Then spin the cranks.  if its now loose (or the same) all the way around then tightening the bolt must be warping the Spider.

Are you using a top hat washer?

The top lip of the top hat washer has effectively moved your crank arm that distance from the spider.

Therefore you need a washer the same width between your crank arm and spider!!

Order - Chainring bolt   -    Spider -     Washer  -  Crankarm Chainring bolt hole.

You can check whether you need a washer with the crankset off your bike by placing your crank arm, top hat, spider on the spindle.   Push it all together with your hand. If the spider isn't flush to the crank arm chainring bolt area then you need a washer to fill the gap because tightening it will only move the spider out of alignment!!  :daumenhoch:



If this isn't your problem then follow Gremlin's advice for the Chainring as that is the most common place to cause alignment problems!!

GREMLIN

  • Guest
Re: Bit of a tight spot (in chain)
« Reply #17 on: October 30, 2008, 03:54 PM »
I've just had a proper look at your pic  ::)

What type of Redlines are they ? Single/twin pinch, model etc...

 :daumenhoch:  G.

sweetbeats

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Re: Bit of a tight spot (in chain)
« Reply #18 on: October 30, 2008, 04:01 PM »
I've just had a proper look at your pic  ::)

What type of Redlines are they ? Single/twin pinch, model etc...

 :daumenhoch:  G.

Unsure of model single pinch 180's though

oldschool rider

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Re: Bit of a tight spot (in chain)
« Reply #19 on: October 30, 2008, 04:02 PM »
IF none of the above works try this :

Items needed : Vice, Rags, Sledgehammer, Cold drink (Beers always good), Loud music, Pc with Internet connection.

Step 1 : Carefully wrap chainring & spider in rags.

Step 2 : Place carefully wrapped chainring & spider in vice and slowly tighten up.

Step 3 : Turn on loud music (Metalica's a good choice).

Step 4 : Open your beer and down it in one.

Step 5 : Start gentley tapping the chainring with sledgehammer in time to the music.






IF THAT DOESN'T WORK TRY STEP 6 !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!























Step 6 : Go to your Pc and look up those lovely people at the RADBMX.COM shop and see if they have a new straight one instock.  :2funny: :daumenhoch: :2funny:

subversion

  • Guest
Re: Bit of a tight spot (in chain)
« Reply #20 on: October 30, 2008, 04:03 PM »
You can always replace the crank arm bolt which stops the spider from rotating with a suitable set screw (grub screw) (no 'head' on it) this will stop the spider rotating as intended but will not pull the spider out of true when tightening it down :daumenhoch:

In my experience the top hat washer should be inserted into the spider from the inside (BB side) not the outside (crank arm side)?

Offline Bigplinky

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Re: Bit of a tight spot (in chain)
« Reply #21 on: October 30, 2008, 04:14 PM »
Mirage power disc, loose it, they are shit. Had about 3 now and not one has been centred correctly. You always have tight and slack spots in a chain it's just the extremety of it that dictates wether you do anything about it or not. Buy a one piece flite ring with correct centre for your cranks and you will notice a big difference.
Why oh why do I still buy kids bikes!

Offline billstup

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Re: Bit of a tight spot (in chain)
« Reply #22 on: October 30, 2008, 04:58 PM »
Just live with it, every one of my bikes, new or old school, have tight/loose spots in the chain and no matter what I do they stay  :(
I see you stand like greyhounds in the slips,
 Straining upon the start. The game's afoot:
 Follow your spirit, and upon this charge
 Cry 'God for Harry, England, and Saint George!'

sweetbeats

  • Guest
Re: Bit of a tight spot (in chain)
« Reply #23 on: October 30, 2008, 05:02 PM »
Cheers Bill It has driven me nuts so I have decided to try and swop it for HUTCH...only built it last week but not feeling the  :smitten:

moley

  • Guest
Re: Bit of a tight spot (in chain)
« Reply #24 on: October 30, 2008, 05:31 PM »
In my experience the top hat washer should be inserted into the spider from the inside (BB side) not the outside (crank arm side)?

Not if your top hat is deeper than the spider/chainwheel.   Then you have to put a Bowler hat (thingymajig) washer on the inside so it can tighten up!!

Thats how I noticed it getting pulled out of alignment!!  :shocked:

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