Few questions regarding cam chain and guide replacement

ratsidecar

.060 Over
Joined
Jul 13, 2017
Messages
155
Location
Northern Ireland
Ride
2006 Rocket III
Hi I have been replacing the cam chain, cam guides and cam chain tensioner spring on my 2006 rocket and I have a few questions.

The cam guide that sits next to the tensioner came out very easily from the bottom and I have attached a pic showing where the tensioner was eating into the back of it. The updated replacement pictured next to it is a much stronger looking item.
IMG_20190112_162804926.jpg

IMG_20190112_162718256.jpg


The chain guide on the other side was very fiddly to remove from the bottom. And fitting its replacement looks tricky too. I am thinking of removing the sprocket from the exhaust cam to give me enough room to drop the guide in from the top of the engine, does this seem like a reasonable solution? I am happy enough with rotating the cams back into the correct position for fitting the chain afterwards.
The cam guide that came out was a metal and rubber item, however it is very bendy. The updated replacement is a single piece of hard plastic with no rubberised coating and looks more like something from a toy than a functional engine part. I have included a photo, is this definitely the correct part?
IMG_20190112_162825768.jpg


Hanging the 2 cam chains side by side with no weight on them the original is visibly a few mm longer than the replacement, good thing its being replaced.
 
That's the worst photo ever :) but yeah the top one in the 3rd photo/photo of the non-tensioning cam chain guides looks to be right. Did it come in a bag with a T1234567 type part number on it?

Re removing cam sprockets to get it in, I don't see why not just make sure the sprocket goes back the exact same position.
Fair play if you can get it in or out with removing the cams or head, it's a biatch

May I ask what made you want to change them out?
Also have you a mileage and measurement for the old chain across 23 links?

Since you've the front engine cover off you should probably invest in updating the clutch pullrod etc, maybe even replacing the detent spring
 
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The engine has about 22k on it and was out of the bike and apart last year to get TDSU bearings replaced and the detent wheel and second gear bits replaced with updated parts. I gave the bike a good checking over about 1k miles after getting it back as I wasn't 100% happy with their attention to detail when they were doing the work. The prop stand for the petrol tank was missing and all the wiring was just shoved in on top of the engine and taped into a bundle. It was nice and neat under there before it went in for the work to be done. They never noticed that the cam chain tensioner plunger was almost fully extended and hadn`t had a spacer fitted to compensate either. Which I thought would have been noticed at the 20k service which was carried out about 100 miles before the TDSU bearing collapsed. When I had also mentioned to them about an unusual noise and feeling in the transmission and was told there was nothing wrong with it.

The clutch started slipping shortly after getting the bike back so I got the bits to replace it as well as the cam chain and warp 9.9 mentioned that the guides were updated at some point so figured best to get the latest parts for it. Especially as a TTS kit is going on later this year.

I didn't bother to take a measurement of the cam chain chain drop with weight on it as specified in the workshop manual as it was getting replaced anyway regardless if it was within wear limit or not.

The bottom one in the second photo is the new part.
The top one in the third photo is the new part.
 
Spent the last few days getting on with the work on the bike. Found some nasty things and then some good stuff happened.

1. Wasn't able to get away with just removing the cam sprockets to fit the non tensioning guide and had to take the cams out. Fitting the new guide wasn`t much of a problem after they were removed. Getting the engine timed up again went okay with the cam alignment tool and all the marks were easy to see.

2. After the cams were out I took a look at things, lots and lots of heavy scoring on the cam ladder, the cams themselves and the inside of the head where the cams run. I presume this is due to debris ending up there from when the output shaft bearing went and the gear on it got the edges of the teeth chipped off. The scoring was most severe above the cylinder at the rear of the engine, not as bad in the middle and much lighter above the front cylinder. Its far past the feel it with a fingernail stage its more like can feel the scores with your elbow stage! A bit alarmed by this I cut open the oil filter to have a look inside, thankfully there was no fresh metal in it so there doesnt appear to be any ongoing loss of material..............for the moment
cam1.jpg

cam2.jpg

score1.jpg

score2.jpg


3. I put it back together for now with the new cam chain, guides and tensioner spring. Then I managed to find a place that was clearing out a stash of triumph parts and got myself a brand new and never been fitted bare head from their old stock. It may be an early one as it is silver. When the scored up one starts giving problems I can put the new head on with a fancy set of cams for a nice upgrade. Hopefully I can reuse the valves and springs etc from the one thats currently on the bike and will just need to buy stem seals and a head gasket for it.......... Theres no point putting my scored cams in a shiny new head or it will damage it too.

s-l1600 (1).jpg
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4. Next job was onto the clutch which had been slipping so I was only able to ride the bike gently to try and preserve what was left of it till getting a chance to replace it. The friction plates were quite badly burnt and the steel plates were blackened on the surface with sexy purple/blue inner teeth on them. Things must have been getting toasty in there. Measuring the steel plates for warpage showed one of them to have close to 1mm warp in it and three more to be warped to around 0.6mm. The rest were within tolerance but I managed to get a new full set of replacements for about a third of what they should have cost from another place having a clearout. So new steel plates, new ebc friction plates and a set of stiffer ebc springs should have the clutch as good as new.
warpplates.jpg
burnplates.jpg


5. On to the fun stuff, got the radiator fan and shroud cut down and transferred over to the new TTS radiator, oil cooler bolted on, and a nice new set of samco silicone hoses and clamps attached. It will be a while yet before the supercharger goes on as I want to have the use of the bike for the spring and summer first so it made sense to do some of the stuff now while things were apart. All the holes lined up nicely although the shroud did need to be spaced off the radiator by 2mm with washers to stop it pressing into the fins. A few of the rubber flaps on the back of the shroud were torn on their attachment points but a little drop of super glue and they are secure and ready to flap again.
radiator.jpg


6. Then I plumbed in the boost/vacuum gauge to the spare vacuum port on the centre throttle body, routed the hose nicely and cable tied the gauge in position temporarily until the bracket I was having made is ready.
gauge1.jpg


7. Next job is to open up the tank and replace the fuel pump with a walbro gss342 that seems to be a popular upgrade, and to try and adjust the fuel sender to get a reading that somewhat resembles how much fuel is actually in the tank. I found some good instructions here: Triumph Rocket III Community

Thats all for now, will hopefully have the bike up and running again by the weekend.
 
Cam scoring is common even without debris ,if the bike is used in lots of slow traffic, idling, with stock idle speed. Set the idle to 900rpm or 925rpm, to add oil pressure. Use oil with a 50 on the last number. eg 15/50 instead of 10/40.
 
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