Firestorm odd noise?

[sirch345]

I was only keeping you guessing ..................................................................okay I ran out of time this morning to post the details.

I was delighted and relieved when I found out what the cause was, but a little annoyed with myself I hadn't thought about this sooner.


The culprit was down to the standard rear CCT spring starting to lose it's tension. This meant the Stopper Rod I fitted had no clearance at either end of it meaning both ends were touching the CCT corresponding components when the bike was on the overrun. In that state the Rod gave a solid stop for the cam chain to bang up against, had the Rod not been there this noise would not have appeared, the CCT plunger would have most likely retracted further.

As some of you will know the pressure placed on the CCT by the cam chain is not a constant force, it varies. I'm assuming this is due to the fact more tension is placed on the CCT side of the VTR cam chain when it has to open the valves, and less tension when it's not operating the valves in each cycle. This creates a sound just like a hammering effect on the CCT. The reason I have come to that conclusion is when I had a CCT spring fail with my Stopper Mod fitted (some of you may remember that), the noise it made was at the same timing as in my Odd Noise recording although most definitely much much louder and happening as soon as the engine was started, that was why I didn't connect the two sooner.

I modified a standard CCT into a manual CCT just to see if my theory was correct. I was more interested in seeing if this was the problem first. I got that fitted yesterday and finished putting the bike back together today, then road tested it.

So we got there in the end.

I'm very happy I didn't have to take the engine out and start stripping that down.

Many thanks to all who contributed in helping me to sort this issue out (you all know who you are ), very much appreciated,

Chris.

[Watty]

glad you're sorted Chris

[sirch345]

glad you're sorted Chris

Thanks Andy, me too

Chris.

[fabiostar]

happy days great to see you got to the bottom of it

[tony.mon]

That's a useful piece of info, why not write it up and add the the cct thread?

[AMCQ46]

Some perseverance there Chris And back to the ccts in the end, they never fail to make our life interesting

[sirch345]

happy days great to see you got to the bottom of it

The not knowing what it was, was starting to do my head in, thanks Rob

That's a useful piece of info, why not write it up and add to the cct thread?

I had thought about linking this thread to it, I did wonder though if I add a post to that thread if anyone would think about looking there if they developed the same Odd Noise Any suggestions where to add it Tony or anybody else

Some perseverance there Chris And back to the ccts in the end, they never fail to make our life interesting

Well you can't give up can you Al it had to be found.
They never fail to make our life interesting, was not what I was thinking at the time

Chris.

[tony.mon]

That's a useful piece of info, why not write it up and add to the cct thread?

I had thought about linking this thread to it, I did wonder though if I add a post to that thread if anyone would think about looking there if they developed the same Odd Noise Any suggestions where to add it Tony or anybody else

Chris.

Just add a post to that thread telling people to search for "odd noise" should do it, I would have thought.

[sirch345]

That's a useful piece of info, why not write it up and add to the cct thread?

I had thought about linking this thread to it, I did wonder though if I add a post to that thread if anyone would think about looking there if they developed the same Odd Noise Any suggestions where to add it Tony or anybody else

Chris.

Just add a post to that thread telling people to search for "odd noise" should do it, I would have thought.

I've added a post here with a link in it Tony:- viewtopic.php?f=31&t=19416&p=451387#p451387

Chris.

[Peeb]

I should have responded sooner. IF you are a stopper mod user AND there is a fresh noise suspected to be cam chain, the first thing to do is remove the hex bolt from the end each CCT and insert a small screw driver till it engages. You should be able to turn the CCT (clockwise) and feel the spring tension as you back the the CCT into the stopper. If you don't feel spring resistance, the spring has broken, unseated, or the stopper mod rod is too long. 1/4 turn (IMO) yields enough slack so the spring tensioner can work but not so much that the cam chain can jump teeth.