FIX the knocking

To knock or not to knock

to suffer the sound of something !! 

what I thought was going to be a never ending story!!

as some will know I have had a noise problem in the Velo a knocking noise. and reported in on face book about it.

well like all good story's there must be an end and I think I have found  the end. 

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I have been a Bit quiet about the knocking noise, as every time I declared I had got rid of it it came back! I have learnt a lot over the last few weeks, and realised it looks simple and is in a way, but slowly I began to realise it’s a balance of all things, and whenever I adjusted one thing all the rest needed brining in  to line and balance

I will not go through how I ended up running around and around and not getting to the point of it or even finding out what it was making the noise! I had made to many adjustments one after the other without realising the knock on affects. So it got more confusing. The final realisation cam last night after I took the Mid drive out for the second time, there was a little movement  in the gear pack cassette I wanted to re check, and fortunately one of my past bikes had the same cassette so I had the right tool to give it a tweak titan, which I did ,.

Then I had a light bulb moment!  I had been thinking along the same lines on working on a bike or trikes, in mind  so had a cup of Tea and contemplated  on what I had adjusted and moved and checked, then I put it all back and started with the front rings, then the tension adjuster  and tubes, I had played  around with the seat as well as I had found that the adjustments made had resulted in the top chain touching the underneath of the seat! I took the spacers I had put behind the guide wheel out,  took the seat up at the front and checked my leg  length that in its self-maid a lot of difference to the noise  it would turn out.

I had taken two links out of the chain which took the chain slap out, and took the top tube out as to it coming loos and it was not needed as without the chain  slap it does not touch my leg. OK I set the did drive in connecting the chains on the cogs and making shore it was set in correctly seated, then adjusted the derailleur arm, the derailleur hold the  derailleur its self in its own setting .

Then I set about checking everything again in s in tern I set the derailleur loos and I knew the cable adjustment would be somewhere around correct I adjusted the derailleur arm to take the derailleur cog away from the gear cassette to a gap I thought about right, (this is where others can help me, I am not shore of this gap I set it by trial and error) then I adjusted the derailleur its self on the arm to a straight setting so the word on the  derailleur where straight  the  derailleur cog ran across the gear cassette straight checking the clearings of the     derailleur cog with each cassette gear, with that set, I went over the set up again starting with the front rings derailleur setting the guide wheel and a tension chain arm.

I held the back of the Velo up on a axial stand and went through the gearing   adjusting the cable adjustment on the derailleur until it was changing correctly on to each gear, I noted that the gearing was harsh so again adjusted the gap of the   derailleur arm and then the derailleur again until it sounded correctly smooth and not so harsh in its jumping from gear to gear ring up and down.

On the largest gear and the lowest gear I checked the arm on the end of the derailleur was just clear of the chain on high and low gearing. So with all this set, I did one more check around all the parts, the last thing I checked was the seat to discover the top chain on the high gear the chain was touching the bottom of the seat So I adjusted the height of the seat at the front and then pushed it the front of the seat forward a little so the chin was clear and the seat was still sitting on the frame with the rubber supports I had put in so the seat top to bottom was supported.

OK again I went through the lot again and checked everything and I rolled it out of the garage for a test ride, well Pleased it felt right and sounded right, no knocking but I had been there before, the cable to the derailleur wanted a tweak and the gearing settled down so I took it back and re installed all the side covers and items I carry, and then took a long ride I did 10 miles and gave it some welly as hard as I could to see if I could provoke the knocking noise but at last it seems to have gone.

I came back to the garage and checked it all again and nothing had moved, all was well so I decided to call it a night. One the ride into work it ran well still no knocking noise just the sound of the chain on the front and the tension  arm Nice one and the seat adjustment was fine to on the leg length.

During this time I put to work some of the suggestions from Harry into thought or practice which was a help to get me to understand the grate pitcher of it not just one part at a time. I had washed out the back free wheel with a cleaner and then re oil it with light oil as heed suggested as this may have had a add to the noise,. But in the end I believe it was a collection of things creating the noise not just one part  but a few thing acting on one part. I love the challenge and I will not give up, when I got it ran perfect but as it wore in looing its tightness I did not follow that up but let it then adjusted the wrong things without understanding the knock on affects.

 

I am still not shore if there is a correct gap between the   derailleur   cg and the gear cassette or is it just trial and area ? May be someone can let me know as with the trikes I keep them all the same as I got them new  I have a little stick at the right length to set them if I ever move them.

 

Well roll on this week ends ride.  And thanks for all the suggestions I have had all along with this, except for one suggestion as it would be just to painful!