Rattling noise - Timing issue?

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FinStorm
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Rattling noise - Timing issue?

Post by FinStorm »

Hello, first post as I'm a new firestorm owner since couple of days ago.
But this time I actually read a little BEFORE I bought something, and ended up doing the Stop Mod at seller (brother in law) before driving home the bike (400 km).
It has original auto CCTs and 34000km.
The thing is I almost f**ked it up as I was rushing and forgot to turn the engine 450° before starting to remove the front CCT.
I had loosened the front CCT about 5mm when I realized I had forgot to turn it.
Didn't hear any clear sound of cam chain jumping, but the smile was very far away while putting it back together.

When done, I turned it over several times and no strange sound or resistance.
Fired it up and went for a short test run, everything seemd ok and I drove it home.

So yesterday I went out for a short trip and suddenly I heard a weak rattle which seemed to come from the front of the bike while driving really slow without any throttle or just standing still at idle.

The sound can be heard here:
https://whyp.it/t/vtr1000f-66127

I hadn't had the front valve cover removed while doing the Stop Mod, but know I really wanted to have a look at the timing of the front cylinder.
Doing all the stripping and carb removal was something a really wanted to avoid.
Always afraid I will forget to put something back (similar to what happened with the removal of the front CCT) or break someting.
After a couple of hours I found an easy way to get to the upper (difficult) bolts of the front cylinder valve cover.
whit a long enough (~15cm and narrow) shaft for the 10mm socket and going above the cooling water pipe between the radiators.
Really easy and quick, you need to turn the front wheel away from the side you are working on to get better room with the 1/4 ratchet.

Image
Image

I didn't, however, remove the cover completely. Only lifted it as much that I could see the timing marks on the sprockets.
So, I don't think there have been any jumped theet, but when FT is exactly on the timing mark, the FI and FE on the sprockets aren't perfectly in line.
To get them as I would believe is perfect I had to turn the engine almost beyond the "FT" mark.
Picture below:
Image
Image

With the timing mark at the correct position the FE mark looked as this (FI offset about same but below the edge):
Image

I also checked the CCTs with the lock key if the spring would have failed (while at TDC compression stroke for respective cylinder).
Springs were ok. But the front CCT MAYBE felt a bit jammed at first, but once turned a bit it then felt ok.

Is this normal "tolerance" for the timing marks or has something happend?
According to VTRDark they usually are a bit off, but how much is ok?
It doesn't have to be spot on and in fact most off them are slightly off by a few mm because of stretch in the cam chain from wear and tear.
viewtopic.php?f=31&t=28583&start=135

Could it be the CCT failing or problem with it?
Adding too long rod in the CCT when I did the Stop Mod I assume would only make the cam chain tighter, while the sound would indicate looser chain?

Any help or idea appreciated!
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AMCQ46
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Re: Rattling noise - Timing issue?

Post by AMCQ46 »

I did once have a light rattle which turned out to be the stopper spacer vibrating inside the CCT . It would only be obvious when idling, and only faintly, but once I could hear it it had me worried

Because I used aluminium tube, it was actually wearing the stopper, and the shorter the stopper got the more it could rattle.

Fixed it by redoing the stopper to the specified wind back but using steel rod.
AMcQ
FinStorm
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Location: Finland

Re: Rattling noise - Timing issue?

Post by FinStorm »

That one I hadn't thought of. Thanks.
Any good idea how to prevent vibration to check if that would be the case?
I could of course remove the stopper, but I wouldn't be completely comfortable with that. I've been arguing with Murphy too many times.
Maybe put a small amount of grease on the rod? Which btw is a non-threded part of an M8 bolt.

Maybe I also could put her back together and see if the noise would be heard when the engine is cold also.
When I heard it the engine was warm and after that ride it has been apart for "investigation"..
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sirch345
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Re: Rattling noise - Timing issue?

Post by sirch345 »

I don't think the valve timing is out enough to worry about going by your photo showing the F/E mark just above the cylinder head line. Basically if the marks are out enough as in over one tooth of the cam sprocket then it needs correcting, but yours isn't showing to be that much out, so I would leave it where it is.

Listening to your audio clip, it's a job to pinpoint exactly what the noise is. Do you think the noise was there before you did the Stopper Mod :?: It's just now you're listening for everything :)

You could try removing the end bolt on the front CCT, then drop a slim flat bladed screwdriver in the CCT end where you removed the bolt from, you then need to turn it a little so you feel the tip of the screwdriver blade drop into the slot of the worm/screw of the CCT. Then start the engine, with the engine running turn the screwdriver clockwise until it stops turning which should be around 1/2 to 1 full turn providing you fitted the Stopper correctly as in this link: viewtopic.php?f=31&t=19416 I wouldn't turn it anymore than 2 full turns if that's possible, or if you hear the engine starting to rattle due to the cam chain being over slack don't go any further.
That should have then taken up the slack of the Stopper spacer you fitted, and if it's the Stopper spacer that is making the noise you're hearing as Al (AMCQ46) mentions then that will stop that happening.

I'm wondering when the valve clearances were last done :?:

Chris.
FinStorm
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Location: Finland

Re: Rattling noise - Timing issue?

Post by FinStorm »

Thanks for you replay Chris.
Glad you think the timing is ok :)

Your guide was followed to the letter, except the "near miss" with the front CCT.
Regarding the valve clearance I suppose it was done during the 24000km service which apparently have been done.
I also have receipt on that, but there's just a note that the "24K service" done. Has about 35000km by now.
Probably I'll also remove the front valve cover completely now also to check those.
The only thing I'm a bit unsure about is how difficult it will be to get the upper (right side) bolt back, as you can't really see the bolt, and the socket didn't hold it very thight. The bolt also has to be aimed exactly straight back in, hopefully won't be that big problem.

Don't get me wrong now.
I've read probably close to 1000 posts on this wonderful forum last two weeks, and I know you two (you and Al) know the bike better than Honda engineers do :wink:
I also thought of retracting the CCT while idling, but I wasn't sure where the "safe limit" is about how much you can retract it.
The stopper mod should prevent the chain from jumping when done properly so I suppose retracting against the stopper should be safe, as you suggested.
But if you retract it "2 full turns" it would equal 10mm, if KermitLeFrog is correct in his statment.
The worm thread is quite coarse and one whole turn is 5mm of movement.
http://www.vtr1000.org/phpBB3/viewtopic ... &start=105

10mm is the same as the length of the spacer I made for the front CCT, so 2 full turns would be the same as retracting the CCT fully, if the spacer wasn't there. That wouldn't feel safe.

I've only been working on old tractor engines before, cam chain and CCT works are new to me :P
Will try to find time for the job later today.
And thanks again for your help!

..also realized now that this topic maybe should be in the Workshop. Feel free to move it if you like.
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MacV2
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Re: Rattling noise - Timing issue?

Post by MacV2 »

Front cam cover removal... Drop the oil cooler & then its bracket. Then just push the hose out of the way...

Once the bolts are out wiggle the cover out forwards.

It's tight but doable...

Just make sure the D shaped bits on the gasket sit in coroctly when you reinstall.

Do not over tighten the cam cover bolts...They like to snap IIRC tourque value is 10Nm but check the manual first...
Making up since 2007, sometimes it's true...Honest...
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sirch345
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Re: Rattling noise - Timing issue?

Post by sirch345 »

FinStorm wrote: Sat Aug 07, 2021 7:30 am Thanks for you replay Chris.
Glad you think the timing is ok :)

Your guide was followed to the letter, except the "near miss" with the front CCT.
Regarding the valve clearance I suppose it was done during the 24000km service which apparently have been done.
I also have receipt on that, but there's just a note that the "24K service" done. Has about 35000km by now.
Probably I'll also remove the front valve cover completely now also to check those.
The only thing I'm a bit unsure about is how difficult it will be to get the upper (right side) bolt back, as you can't really see the bolt, and the socket didn't hold it very thight. The bolt also has to be aimed exactly straight back in, hopefully won't be that big problem.

Don't get me wrong now.
I've read probably close to 1000 posts on this wonderful forum last two weeks, and I know you two (you and Al) know the bike better than Honda engineers do :wink:
I also thought of retracting the CCT while idling, but I wasn't sure where the "safe limit" is about how much you can retract it.
The stopper mod should prevent the chain from jumping when done properly so I suppose retracting against the stopper should be safe, as you suggested.
But if you retract it "2 full turns" it would equal 10mm, if KermitLeFrog is correct in his statment.
The worm thread is quite coarse and one whole turn is 5mm of movement.
http://www.vtr1000.org/phpBB3/viewtopic ... &start=105

10mm is the same as the length of the spacer I made for the front CCT, so 2 full turns would be the same as retracting the CCT fully, if the spacer wasn't there. That wouldn't feel safe.

I've only been working on old tractor engines before, cam chain and CCT works are new to me :P
Will try to find time for the job later today.
And thanks again for your help!

..also realized now that this topic maybe should be in the Workshop. Feel free to move it if you like.
I'm impressed by how much research you have done on this forum, you certainly sound as if you have your head around what can happen with a failed CCT, and what the function of a standard cam chain tensioner is.

I fully appreciate your concerns of backing the tension off of the CCT plunger with a screwdriver should the cam chain become too slack. Theoretically though seeing as you followed my guide on carrying out the Stopper Mod to the letter, I doubt you will be able to turn it more than 1/2 to 1 full turn before the spacer rod you fitted stops you going any further,

Chris.
FinStorm
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Location: Finland

Re: Rattling noise - Timing issue?

Post by FinStorm »

So, found a couple of hours in the afternoon.

Removed the bolts from the front valve cover and lifted it as much as possible.
Tight, but actually got the valve clearance measured. However, i can't recomend doing it this way, not maybe the most exact and reliable front measurment :roll:

REAR
EX = 0,30
IN = 0,10 (went easy, but 0,15 didn't go. realized later there was a 0,02 blade I could have used)

FRONT
EX = 0,30 (not really tight, but 0,35 didn't go)
IN = 0,15 (tight)

So those seems ok if tolerance is ±0,03, except rear inlet that might have been on the limit of tolerance?

When the bike was in one piece again, I went for a shorter test run ( ~5km) to get her up in temp, no rattling sound.
Later in the evening I again went for a little longer drive, but no noise any more :thumbup:

Only thing a actually have done is having had the rear CCT out for inspection and excercised the front CCT still mounted.
Can't do much more for the moment as there is no noise right now, but I will for sure keep my ears open.
If happening again I'll know were to begin.
Little annoying not knowing what it was..

What I've learn't from this:
Checking the timing without removing carbs etc, very doable by going in through the front.
Checking valve clearance, or anything requiring the two upper bolts on the front cover to be removed, BIG NO NO.
Might be much easier by removing the oil cooler as MacV2 said, but stubborn as I am, I probably worked an hour to get those two back.

Haven't been riding many bikes, ~11 years since I sold my Thundercat, and an old kawasaki before that.
But this bike I'll never sell. If you begin to have second thoughts, you just have to go out, fire it up and listen to the Devil cans singing :twisted:

Many thanks for the help!
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sirch345
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Re: Rattling noise - Timing issue?

Post by sirch345 »

FinStorm wrote: Sat Aug 07, 2021 10:35 pm So, found a couple of hours in the afternoon.

Removed the bolts from the front valve cover and lifted it as much as possible.
Tight, but actually got the valve clearance measured. However, i can't recomend doing it this way, not maybe the most exact and reliable front measurment :roll:

REAR
EX = 0,30
IN = 0,10 (went easy, but 0,15 didn't go. realized later there was a 0,02 blade I could have used)

FRONT
EX = 0,30 (not really tight, but 0,35 didn't go)
IN = 0,15 (tight)

So those seems ok if tolerance is ±0,03, except rear inlet that might have been on the limit of tolerance?

When the bike was in one piece again, I went for a shorter test run ( ~5km) to get her up in temp, no rattling sound.
Later in the evening I again went for a little longer drive, but no noise any more :thumbup:

Only thing a actually have done is having had the rear CCT out for inspection and excercised the front CCT still mounted.
Can't do much more for the moment as there is no noise right now, but I will for sure keep my ears open.
If happening again I'll know were to begin.
Little annoying not knowing what it was..

What I've learn't from this:
Checking the timing without removing carbs etc, very doable by going in through the front.
Checking valve clearance, or anything requiring the two upper bolts on the front cover to be removed, BIG NO NO.
Might be much easier by removing the oil cooler as MacV2 said, but stubborn as I am, I probably worked an hour to get those two back.

Haven't been riding many bikes, ~11 years since I sold my Thundercat, and an old kawasaki before that.
But this bike I'll never sell. If you begin to have second thoughts, you just have to go out, fire it up and listen to the Devil cans singing :twisted:

Many thanks for the help!
Well done in checking the valve clearances, at least you now know yourself they back up the paperwork you have.

I have removed the front cover from the front before, I know how much of a struggle it is to do, goodness knows how you managed it without removing the oil cooler from it's mounting point first. I find removing the front cover much easier by removing the carbs first and going in that way.
FinStorm wrote: Thu Aug 05, 2021 10:29 pm I also checked the CCTs with the lock key if the spring would have failed (while at TDC compression stroke for respective cylinder).
Springs were ok. But the front CCT MAYBE felt a bit jammed at first, but once turned a bit it then felt ok.
I have experienced that sort of jammed bit you mention on a fitted CCT before too,

Chris.
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