# KMX Gears 3x8=21 ?



## Andrew1971 (7 Apr 2016)

Hi all
Got a little problem with my KMX. I have taken the two top chain tube's off because they were noisey.
So i take it out for a spin put it into 8th gear it was noisey me think's rear deraileur need's adjustment
I get home it's the chain rubbing on the frame. No matter i much i adjust rear deraileur it will alway's rub on frame in 8th gear only. So it rub's with or without chain tube on. Small design flaw !!.
So i can't use 8th gear hence 3x8=21 Has any one else got a simular problem with their KMX
Many Thank's
Andrew


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## Lanky (7 Apr 2016)

I would be thinking of a trip to Cowleys bike shop. Has it always been like that.


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## numbnuts (7 Apr 2016)

I have the Cobra and it's OK …....I think......... as I get no noise


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## Andrew1971 (7 Apr 2016)

Yes. as iam getting better i have been getting into the higher gears that's when started showing up.
I have a couple of idea's now i had time to think about it.
@numbnuts how close is your chain to frame.
I bet i have the dodgy one. Look's like phone call to KMX and just fitted new tire's too and some other mod's too. Or fix it myself.
Many Thank's
Andrew


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## numbnuts (7 Apr 2016)

Andrew1971 said:


> Yes. as iam getting better i have been getting into the higher gears that's when started showing up.
> I have a couple of idea's now i had time to think about it.
> @numbnuts how close is your chain to frame.
> I bet i have the dodgy one. Look's like phone call to KMX and just fitted new tire's too and some other mod's too. Or fix it myself.
> ...


It's very close, but it's not rubbing, well the paints not marked


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## Andrew1971 (9 Apr 2016)

Cheer's numbnuts for having a look. Look's like it's down to the metal on mine
Many Thank's
Andrew


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## numbnuts (9 Apr 2016)

Andrew1971 said:


> Cheer's numbnuts for having a look. Look's like it's down to the metal on mine
> Many Thank's
> Andrew


You have the same cassette 32x11 make sure your back wheel is seated well in the slot as that would make the smallest cog lower down


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## Andrew1971 (9 Apr 2016)

Hi numbnuts
Just went out and checked wheel fully in and guess what the new cassette I put on is 
12-23 and still rubs  
Many Thanks
Andrew


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## Andrew1971 (12 Apr 2016)

A little update managed to get her a lot quiter but still rub's. 
I going to put some tape over the mark on the frame and see what happens.
Many Thank's 
Andrew


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## numbnuts (12 Apr 2016)

I think the only way you can stop it rubbing is not to use the lowest gear.
As I all ready stated mine is very close, but it doesn't rub and is very quiet.

PS can you post a photo please


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## voyager (14 Apr 2016)

stupid question here 

have you tried to put a spacer washer on the spindle to bring the cassette away from the dropout 

I will get my coat 

regards emma


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## e-rider (15 Apr 2016)

reading this post it's hard to picture exactly where the chain is rubbing, but, it could be that the frame was designed for 7 speed cassettes and the 8 speed is just 1 or 2mm too wide - you might be able to adjust it out by playing about with the rear hub axle configuration

it does sound like the design of the frame isn't the best as well


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## numbnuts (15 Apr 2016)

I had another look at mine yesterday as I was cleaning it and I think it is down to them using box section for the chain stay and the tolerances are too tight = a design fault !!!


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## Andrew1971 (15 Apr 2016)

Hi All
Some picture's





The bottom pic is of chain hiding the mark it made on the frame.
That's the result from the chain rubbing even more noisey with a 11t put 12t to stop it and did not.
Many Thank's
Andrew


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## numbnuts (15 Apr 2016)

Ouch that is tight, maybe get in touch with KMX and send them the photo


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## Smokin Joe (15 Apr 2016)

I've pondered about removing the rear tube on my performer, splitting it lengthways and wrapping it round the chainstay instead. I've not been brave enough to try yet, but I may get another tube and see how it looks.


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## Andrew1971 (1 Aug 2016)

Hi All
An update it turn's out the rear of the frame is a little twisted. So rang KMX had a good chat and
new frame and new rear wheel was sent under warranty no charge. Could not have wished for a better 
result. Now i have all gear's 
Andrew


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## Lanky (12 Aug 2016)

Am I right to presume it is all working as it should be now?


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## numbnuts (12 Aug 2016)

Andrew1971 said:


> Hi All
> An update it turn's out the rear of the frame is a little twisted. So rang KMX had a good chat and
> new frame and new rear wheel was sent under warranty no charge. Could not have wished for a better
> result. Now i have all gear's
> Andrew


Good result and well done KMX


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## byegad (13 Aug 2016)

Nice to hear of great service. +1 to KMX.


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## Andrew1971 (13 Aug 2016)

Took the KMX out today on a longer run 67mile's and what a difference the new frame and wheel has made.
It freewheels so much better, easier to pedal. it run's a straight line, more stable at higher speeds.
Last but not least i have ALL gear's now. It's a pleasure to ride. So all sorted now.
Andrew


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