Bonneville America Forums Forums Technical Forums General Tech Valve Train Noise

So I'm getting ready to tear into my valve train. It's always had a little tick to it that worsened when it got hot, but now it's to the point where I think something's not right. I'm waiting for the feeler gauges to come in that I've ordered, and I'll check some clearances. I've been told to check my backlash springs, but need some help on how to do this. Once they're unsprung how will I get them resprung?

Special pins are available to hold the backlash springs in position, or you could make your own. It's easiest to do before removing the cams. You can put a 6mm diameter steel pin, approx. an inch long, in a a drill, and use a file to turn down one end to 4mm. You'll need two of these. Very easy to do. Insert then in the holes in the cam gears and you're good to go.

I know that part, my question is to check those springs ie removing the backlash springs to check them, I'll have to unpin the two gears. How should I go about checking those springs? Don't I have to unspring it?

IF one is bad/broken. there will be no tension on the pin when you pull the cam out. I really doubt that's likely to be the case. If you feel the need to unspring them, you can (carefully) put a flat screwdriver in the gear teeth and twist it to align the holes and get the pin back in. It's not that difficult.

Thanks man... I guess I just needed some encouragement. I've never been in the valve yet, so didn't know what exactly to look out for.

If you plan on keeping the bike I would just buy the tools.

I have to do it Ian... I'm sorry, but here in a few years 1 or 3, I'll be owning one of them Thunderbirds, and you can't stop me.

I have never knocked anyone for wanting a Tbird just don't want one myself and don't like quite a few points about the bike but that doesn't make those who like it wrong. If we all liked the same thing there would be just 1 make and model of everything weather it be car, truck, cycle, shirt etc..

I know man I was just givin' you a hard time.

The cover is off, and I'm pokin at it with a SAE feeler gauge, but it's not going to cut it. The metric KD should be here... now. I can already tell some are out of tolerance a bit.

I used SAE feelers and just converted.

Poke fun at me all ya want, I'm always down for a laugh even if it's at my expense, just not feeling well today.

There is a handy inch/mm converter on Dinqua's web page. Click on shim calculator, then on converter.

Yeah I know of a few conversion methods, but my SAE set didn't have the precision I like to have. Google actually is one of my fav's. Just type in "convert 4mm to inches", and it'll do it. Throw what you want to at it.

Anyways, I've got my metric feelers, and it looks bad. Two exhaust were fine, but the others were .34, and .31, and 1 intake was at .13 the rest were good. I'll be getting the shims out as you guys read this to see what they are and use dinqua's shim calc. to figure out the new ones. This is actually pretty fun. I already dropped a tensioner pin down inside, but got lucky with a magnet and got it out. Whew!!!

Update to come. Sorry to hear your down Ian. I'll try to keep this interesting for you.

Haven't need Whitworth for the US Triumphs since the 50s, they changed it all to SAE back then. There is always a chance for error weather using metric or not. Just add one more steo and extra chance for error by using SAE gauges. Hey, I like living dangerously. I have a set of metric but the graduations are too far apart for my liking, my SAE are in smaller increments.

I'm just the opposite, my SAE lack in precise increments where as my MM hit everything I need.

So I went to the dealer today Engle Motors. One of the best dealers I have the pleasure to do business with. Just to pick up the shims lacking from the shim bank. They of course have every shim needed for me + every washer / o-ring needed for the oil feed tube, and I told the guy... man a lot of other dealers don't even carry shims, but you've got everything? He said well we're a full service shop, if anyone tells you different, slap em' for me.

I've heard nothing but good things about Engle.

Alright, I'm not so lucky the second time. I dropped the tensioner pin down the hatch. Should I have had the hole cover?.. yes. Did I?.. NO! I've tried a magnet on an extension, but it's down there. What should I do now?

You'll have to try and fish it out with a very thin magnet on an extension. If the pin made it to the sump, you might be able to get at it from the oil drain hole also.

Anybody know if you can access the sump with the clutch side cover off from the side? Any access holes if the oil pumps are removed?

In any event, don't run the engine with that piece in there.

well I've went from the top side all the way to the bottom cam chain gear, and didn't get it. I'm using some strong earth magnets too so if it's close, it's coming out. I'm thinking clutch cover. I need to replace the seal where the clutch rod goes through, and might as well put on the stiffer clutch springs. Surely I can finagle under the basket, and "finger her out".

Ian I think that's going to be my new catch phrase.

I don't think you will get to it from under the clutch cover. This isn't going to be pretty if you can't fish it out from the top.
Can you say "time for a big bore"!

I can say it for sure, but that leather thing in my back pocket is screaming no.

Anyone got a pic of the internals directly behind the clutch cover? I know for sure that it has made it down to the bottom of the bottom. It is nowhere near the cam chain or lower idler gear.

Stories like this make it worth the 140 bucks the dealer charges to make it right.

What about the oil drain plug access?

I think that's what I'm going to do tomorrow. I've got a pretty strong earth magnet that'll hopefully coax it to the drain plug. Wish me luck... I'll be doin this tomorrow morning.

On the bright side, the valves are all fixed.

Dang, that's some bad luck there. I've got my fingers crossed for ya!

This may seem extreme, but you could use a hoist and actually flip the bike over and pray it falls out if you cannot get it at the drain pan.
As for the oil drain, you will have to remove the entire oil pan as there is also a big metal screen inside the motor too.

If you can't get at it from the oil drain plug I'd just unbolt the sump. I had to do that recently. I lost a copper washer down the center of the engine so a magnet was out of the question. I pulled off the sump and there it was.

Didn't know the sump was removable. Good to know.

alright... I've got the clutch springs replaced, and poked around with the magnet with no luck. I then removed the oil pan, and poked her some more. Thanks for the sump suggestion. That'll be my next approach. I'm enjoying this shade tree mechanic's work.

Believe me the thought did run accross my mind that if I was a body builder, I could just pick it up and shake it out like a salt shaker.

It took a lot of work, but I ended up finally getting the pin out with a slim earth magnet duct taped to a piece of wire. I only had to remove the top idler gear, and the cam chain guides to get it. A heck of a lot better than pulling the head, and doin that whole route.

Now it's just the hassle of putting it back together.

Very cool, glad you were able to fish it out with not too much trouble.