Hi
My second post and I hope this may help.
I have owned my CBR from 36,000mls to its mileage now of 85,000mls. Its the time for large amounts of cash to be spent and I am not giving Honda one more penny as far as camchain tensioners are concerned, so I propose the fix I will outline. The work that needs doing includes the dreaded alternator drive chain and tensioner, starter clutch and clutch plates. With these meaning the cases will have to come apart it makes no sense not to do the whole lot. Now in the light of the balancer shaft adjustment post and the favourable results posted some of the noise may go away. I have not had a chance to try it yet but I sent a cheque for £240 for SOME of the parts required only days before seeing it. Ain't it always the way?

Costs are
Starter clutch, alt chain, tensioner £235
Complete gasket set £100
Clutch plates £45
Clutch nut, balance damper rubbers, oil pump chain and various other bits £50

a total of £430 and add another £130 if you were to get a cam chain and tensioner, which as said before I won't be doing this time. And that is all on top of £150 new scorpion exhaust, £90 new front tyre, £36 tax and £25 MOT

Thing is I have had it done at 36000, 54,000, 78,000 and again now at 85,000 @£260 each time! Often within days it has been back to its old ways of sounding sweet or like a bag of nails seemingly without reason.
With this experience and studying the tensioner for many hours I come to the conclusion that its a P###e of c##p. It is just flawed by design. I propose to simply lock up the tensioner from opening mechanically rather than the oil method that don't work. Having put a guy in contact with a whole load of Lathes and mills recently I should be able to get the machining done but it is quite simple

1 Mount tensioner on mill and bore and tap the three hole that pass right though the two tensioner body plates.
2 Extend the arm fully and drill the 4mm hole through the spring end of the tensioner arm
3 Make mount plate
4 Make locking plate
5 Install mount/ locking plate and fix pin to connect with tensioner arm.

With the threaded bars going right across there is no danger of any parts should they come lose dropping down into the crankcase
The tensioner still does its job but is locked from opening/ loosening. Every few thousand miles the locking nut would need to be loosened and then retightened.
Well that's what I plan, hope the pics explain

http://i4.photobucket.com/albums/y14...tensioner2.jpg

the old bird
http://i4.photobucket.com/albums/y14...l/a6223f07.jpg

Cheers
Phil

 

Bad for you having spent that kind of money on services, instead of fuel for fun. A few questions regarding the CCT mod since I haven’t studied how it works, or even seen one. My CCT cold-rattled but I didn’t care since it quieted down a minute or two after firing up.

Which part is in contact with the chain (or chain pusher if any), is it the nose of the CCT at the bottom?

What is the yellow bracket for, is it a security mechanism protecting the CCT to come to loose, securing that the chain slack never goes below a certain value?

Could one weld a nut on the yellow bracket where it meet the CCT body, or at the end where it meets the spring, and use a bolt which is adjusted and locked by another nut (to the welded nut) to limit the movement? If that is correct no new parts has to be fabricated and the mod will be simpler.

I’m sure I must be totally wrong since I'm not clear about the design and function, any comments?

 

Hi Guys,

You've gone to a great deal of effort here. One small point that may help - CBR1000Fs sound like a bag of nails when the engine doesn't idle smoothly - here's why:

It's the oil pump chain. This is a small (like a bicycle chain) chain running from the crankshaft to the oil pump drive. It has no tensioner and is a loose fit so that you can manoeuvre the oil pump into position. When the engine is idling (and not idling smoothly), it slops about and bangs onto the upper crankcase. If you have taken your engine apart, you will see the marks it has made. This is the voice of experience having taken my engine out 3 times trying to cure a rattle when idling (it sounded quiet once above around 2000 RPM). I changed ALL of the chains inside the engine and STILL had the rattle. Then I spoke to Honda's technical department in Slough and they told me about the idling issue. So I bought a Gunson's Colourtune. I already had a carb balancer, and was sure that they were balanced OK. When I looked at the mixture burning with the Colourtune I saw that one cylinder was running a bit weak, one was a bit rich, and the other two were OK. A session on a rolling road would have showed everything to be fine because the average of the 4 cylinders was spot on! After adjusting the carb idle mixtures, the engine sounded sweet and more importantly, QUIET, all the time.

So, before you take your big steps, it may be worthwhile checking the carbs....

 

Hi R1000
The bottom bit is just were the piston below the spring sits and is supposed to be locked by the oil that collects in the resevoir. The actual tensioner blade fits outside the chain and is pulled inwards. When the (yellow) tensioner arm moves clockwise it loosens the tension and anticlockwise adds tension. I looked at many methods and I am sure there are a few that would work but this seems to be a good way without taking the whole thing appart. Also the arm at the spring end moves in an arc so any attachment needs to allow for this. Like all other camchain tensioners the objective is to allow the spring to exert its force but not to be pushed back. Many tensioners use a simple spring loaded wedge that allows movement only outwards. Far to simple for Honda.
It took me lots of head scratching before I could work it out as well.

Cheers
Phil

http://i4.photobucket.com/albums/y14...tuff/iiujj.jpg

 

Hi snotter
Yes the oil pump chain is one of the bits that will be replaced just as a matter of course as the cases are open. I have to split the cases anyway as the alternator chain and starter clutch definitely need doing. Would like not to have to but I suppose 85,000 is a fair mileage.
I know what you mean about engines being noisy when out of balance as my old CB750FA used to sound awful unless balanced. When mine is newly balanced it does make a difference but it just means I can hear the other rattles even better
I think the totality of the rattling with CBR1000's is a combination of bad tensioner design, balancer shaft adjustment, alternator drive chain looseness and as you say oil pump chain ,all compounded by uneven running.
I will certainly look at doing what you say with the colour tune when rebuild time comes around. Saying that all I have done up to now is order some of the parts ( it was just to painful to pay for them all in one lump) cleared the shed and spent too much time at the computer
With all the gripes I still love the CBR1000. Mine is beginning to look a bit tatty but the build quality, paint etc are excellent and I love the overall styling. I was thinking of getting a different bike but the only thing that came close was maybe a CB1000.
Oh I also love the way that motorists seem to think that its a copper behind them. I can only put it down to what they see being the red and white bodywork, dark screen and the two dark air inlets above the headlight looking perhaps like unturned on blue lights. I loose count of the number of motorists that dive out my way even without prompting. Love to hear the comments when they realise its just a fat bloke on a bike

Cheers
Phil

http://i4.photobucket.com/albums/y14...f/e3_12_sb.jpg
http://i4.photobucket.com/albums/y14...f/3a_12_sb.jpg

 

I see, looking forward to your findings when you have fielded the mod and good luck !

 

(Thought it be better to ask here instead of starting a new post)
Is there any known solution for oil pump chain being lose. Mine ate up my shifting drum.

 

Much better you start a new thread - this one is 8 years old - from 2006!!

Cheers, SB

 

Funny enough most other forums I get trolled for starting a new one lol. But a superior has spoken and I shall obey.