Triumphrat

mr.chain · 11-12-2009, 05:24 AM

Any of you guys had any experince with a little engine noise?

I started up my T-Bird the other night and on start up noticed a weird rattle that lasted about half a second and dissapered. It sounded like it came from the bottom of the block. Went for a ride and all was well, however the following morning I started the thing up again just to make sure I had heard something. I asked my dear dear wife (it was 6am) to come into the garage and have a listen just in case I was mistaken, and sure enough she heard it too.

The noise seems to have happened on cold start up but I have not heard it on all cold start ups, only the two instances noted above.

Off to the dealer I went and dropped the bike off. Called the dealer today who assured me that all is well and he didn't hear any noise on start up, but wants to check it out further.

The bike has 1,100 ks was serviced at 800 ks, is running Mobil 1 with plenty of oil, has the TORS tune on standard pipes and air filter and otherwise no problems.

Any suggestions????

Birdy68 · 11-12-2009, 07:01 AM

Hi Mr. Chain

First off - I want you to understand that I DO NOT want to scare you! OK?

It might be something to think/look at?!?
As I said - I don't want to paint things black.

It may just be that you are 4 dl low on oil - just that little bit to lube the valves as things start up... ?

Anyway - I hope it IS NOTHING, and you can sleep at night.
Keep us informed!

kraftdinners · 11-12-2009, 07:20 AM

Hi Guys

Ok nothing about a compressor relief valve in the Triumph workshop manual, only the Exhaust Decompressor on either end of one of the cam shafts which is operated by counter weights at each end to assist with engine starting ..I assume that it keeps the exhaust valve open upon initial start up to decompress the cylinders and "closes" the exhaust valve pretty quick via the counter weights when she fires up.. but no "valve" is involved..hope this helps, not unless "they" were referring to the oil relief valve ..

Birdy68 · 11-12-2009, 07:56 AM

Quote:

Originally Posted by kraftdinners

Hi Guys

Ok nothing about a compressor relief valve in the Triumph workshop manual...

Nooo - not a Compressor Relief Valve, but a Compression Relief Valve, as in...

Quote:

Originally Posted by kraftdinners

Hi Guys

... keeps the exhaust valve open ... to decompress the cylinders..

I bet that that would be the so called 'Compression Relief Valve'

Thanks though, for looking into the Workshop Manual - that reminds me to tell the wife what she should buy me for Christmas.

kraftdinners · 11-12-2009, 10:03 AM

Hi Birdy

I think it utilises the Exhaust valve on both cylinders somehow, the device is located on each end of one of the cam shafts, and I assume at rest it keeps the exhaust valve open in some way ( its not explained in the manual ) it shows an illustration of them, they are operated by counterweights, much like the counterweights in a distributor that alters the timing for startup in a car and on pre electronic ignition bikes, and I assume when the bike fires up the counterweights somehow "close" / alter the exhaust cam to operated normally, well thats my take on it for what its worth, seeing that the OP said the noise came from the bottom of the bike and was told it was a decrompression relief valve, as in a specific device, but the manual shows the exhaust valves are utilised as decompressors for startup .. a neat idea if what I say makes any sense ;-)

mad_angler · 11-12-2009, 03:55 PM

when i looked onto it before i did not think it had a dedicated valve as such like on custom bikes, i did read somewhere about it being part of the exhaust cams bout could not find it again, its very common on big bore bikes, it allows you to run a smaller starter and battery, hopefully its not a common issue, although this could be the reason some people are having starting problems if its not closing correctly

on release valves my friend has a DUX 3000cc v Twin in his custom and that has 3 release valves per cylinder

they are mounted in the head where you can press them

mr.chain · 11-14-2009, 06:02 AM

Well I just thought i'd get back to all about that engine noise that I reckon I noticed. Haven't noticed it since and the dealer had the bike for a couple of days and did not notice any engine noise either, other than the usual. They did not think that whay I may have noticed was anything to do with the decompression valve, but perhaps more to do with injectors. In any event they logged the potential problem in case something goes awry but at this stage all is well.

It may have been the case of rushing my new baby to the doctor on the first sneeze, but I reckon you all will understand that.

Mr.Chain

mr.chain · 12-15-2009, 07:27 AM

Well Thunderbird affecionados, here is the thing. My T Bird continues to make a rattling sound on start up, probably lasts about 1 second and it sounds like the oil is taking that 1 second to reach the top and teh valves. I had the dealer pull the covers off it and test the hydraulic cam tensioner and he reckons that there is a slight movement in the tensioner that accounts for the noise. He spoke with the Triumph warranty manager in Australia whose view it was that this is a normal engine noise on start up and is probably made by many Thunderbirds across the board when started.

So what I would like is for you guys to listen to your bikes on start up, preferably cold, and then post your replies indicating whether you can hear any engine noise, and what it sounds like and how long it lasts for.

If things are not right with my T Bird then I would like to know and get something done about it.

Thanks,

Mr Chain

dazco · 12-15-2009, 11:12 AM

I have never noticed that particular noise, but when new my bike made a lot of noises especially when cold. I can't describe it, but just a lot of inconsistent random noise. I thought that was just this engine's personality. However, in short order that all disappeared completely after one or two thousand miles. You may just be experiencing the thunderbird's unique break in period.

mad_angler · 12-15-2009, 11:44 AM

nope no noise from mine either, i very much doubt its the chain tensioner unless its faulty as its spring mounted as well as hydraulic, the spring takes the tension until the oil pressure comes up,

the exhaust deconpresser wont do it either, very interesting in deed, could be some play in the starter perhaps, can you record the sound ?

something worth trying is disconnect the wire to the fuel pump and turn it over wuth out starting until the oil pressure light goes out, then re connect and fire it up,see if it still does it, this way you have already primed the oil system and will tell you if it is an oil related problem.