Sudden tappety rattle

[MattW]

Hi all,
Got back from a 2500 mile two up European trip yesterday and my 47k 1100 has a rattle that it didn't start out with.

About 750 miles into the trip, after a long alpine pass descent (lots of trailing throttle / engine braking), I noticed that the right hand pot had become very 'tappety' (we'd done a 400 mile motorway thrash and a couple of small passes before this). After an initial panic and thoughts of taking the rocker cover off to 'have a look', I decided to leave it well alone and call ADAC if it actually broke. There was no noticeable difference in performance and fuel consumption remained the same (about 50 mpg). About 500 miles before the trip, I'd fully serviced it and did the valve clearances / rocker end float.

It didn't break and we completed the trip with it probably a little more rattly than when the 'extra' tappety noise started but by the end, I'd become immune to the it I know that running it hard for another 1500k may well have made whatever is causing it worse but in the end it was a judgement call - start tearing into to the engine in a foreign hotel garage and possibly introduce more issues or wait till it became a real problem.

I'm about to clean it and investigate the noise. From what I've read on here, it may well be the pushrods / followers or even cams but I guess I'll only find this out when I start to take it to bits. I'd guess cams and followers aren't cheap (I haven't dared look yet!) but you never know - might just be followers.

Does anyone know if you can remove the cam carrier assembly with the head still on the bike (will save fighting with the exhaust and a new head gasket) - it looks possible?

Cheers
Matt

 

[Steptoe]

Does anyone know if you can remove the cam carrier assembly with the head still on the bike (will save fighting with the exhaust and a new head gasket) - it looks possible?

Cheers
Matt

Yes..

 

[MattW]

Yes..

Great - thanks Steptoe

 

[MattW]

Ok, got the rocker cover off and checked the valve clearances. Both inlets and exhausts have the appearance of having opened up by about 0.05 mm. All adjusters etc are tight and secure and the clearances were correctly set and were 'normal' sounding and quiet about 1000 miles or so before it suddenly went noisy on my trip.

This sudden increase of valve clearances has to have come from somewhere so I'm going to remove the cam carrier and take a look. Looking at Steptoes head gasket how to and the clymer manual, the procedure should be just like removing the head as the head bolts (along with the other smaller bolts) also secure the cam carrier but the head stays in place. I guess there's a risk that the head gasket won't reseal properly, especially as mine is the original '94, but I'll have to deal with that if it happens.

Am I thinking along the right lines here?

Thanks

Matt

 

[MattW]

Forged ahead and removed the four big head bolts, cam chain sprocket and three cam carrier bolts but despite some persuasion with a rubber mallet, the cam carrier doesn't want to come out.

Am I missing something here?

As ever, any advice greatly appreciated

 

[topcat2006]

Yes, you have not undone all of the bolts. From memory you have to do the 5 that are left too.

Tom

 

[Edward]

Matt, this is honestly not meant as a snide comment but from your last post would you not be better taking it to someone who may better know what they're doing?

 

[MattW]

Matt, this is honestly not meant as a snide comment but from your last post would you not be better taking it to someone who may better know what they're doing?

I've had the bike to bits in various stages over the last few years, including replacing a head gasket (other side), swing arm, para lever bearings, gearbox output shaft seal etc - I'm certainly no Steptoe but I'm not afraid of spanners.

I've just discovered my issue removing the cam carrier was that I believed the stupid fecking Clymer manual. Looking at Spa's rebuild thread I saw a picture of his bare cylinder head and realised that two bolts that the clymer manual says not to touch actually hold the cam carrier in (5 bolts in total).

I've just removed these two and the cam carrier assembly is sitting on my bench.

The good new is that the camshaft looks perfect - no significant wear to the lobes and the bearings feel good.

The pushrods appear fine at first glance but I've not tried them to see if the ball ends are loose. I've yet to check the followers...

 

[Edward]

I've had the bike to bits in various stages over the last few years, including replacing a head gasket (other side), swing arm, para lever bearings, gearbox output shaft seal etc - I'm certainly no Steptoe but I'm not afraid of spanners.

I've just discovered my issue removing the cam carrier was that I believed the stupid fecking Clymer manual. Looking at Spa's rebuild thread I saw a picture of his bare cylinder head and realised that two bolts that the clymer manual says not to touch actually hold the cam carrier in (5 bolts in total).

I've just removed these two and the cam carrier assembly is sitting on my bench.

The good new is that the camshaft looks perfect - no significant wear to the lobes and the bearings feel good.

The pushrods appear fine at first glance but I've not tried them to see if the ball ends are loose. I've yet to check the followers...

Good luck with it Matt, the buttons on the pushrod ends can loosen but may not be obviously loose.
Have a look at this.
http://www.youtube.com/watch?v=pRXeaequvzk

 

[MattW]

Good luck with it Matt, the buttons on the pushrod ends can loosen but may not be obviously loose.
Have a look at this.
http://www.youtube.com/watch?v=pRXeaequvzk

Thanks for that - I'll check them tomorrow (packed in for today). Must admit, I had visions of a knackered camshaft (too much time mentally chewing it over while riding around on our trip) so to find it perfect is a relief. I'll take out the camshaft and take a look at the followers also.