Britbike forum Forums British Motorcycle specific Brands Bsa bulletin board B44 header pipe install and timing question

So I have the new setup with the clubman bars. Not a bad position for riding. Everything works as it should.

So today I'm working on the timing and carburation. It seems to want to leak at the header/head union. I've done this twice over now and I really thought I had it but it seemed today like it was opening up again. I have used copious amounts of "Goop" for high temp exhaust sealing. It has the fined collar and I put on a hose clamp to keep that in place. Am I missing something? How do I get a lasting seal at the head pipe?

The ignition seems to break up at 3000ish RPMs, and I think it needs more advance. It could be the poor head pipe leaking air. Any more and I get kick back from the kick start, with seems to indicate too much timing. Any tips on getting the timing spot on? At this point, it pretty much starts with ease, and I like having the timing there.

Lastly, while I don't have a working rev counter, I can tell roughly when it is 1000 rpm and 3000 rpm. What is a safe range to take the rpms up too before I risk damage? The after market open muffler sounds awesome. I'll try and get pics and video this weekend.

It's really coming around and is a fun ride.

https://photos.app.goo.gl/SKS1ztqhzp5CHs4HA

Also, what's the trick for getting the sump plate to seal? This is the only bike I have that leaks. Which is fine, but I'd like to cut down on the volume. Thicker cereal box?

Thanks for looking

Linden

Going thru the points.
The finned clamp doesn't do any sealing, it is just from show (and a little cooling). The exhaust is simply push fit. Unfortunately, the soft ally of the head gets all worn by the hard exhaust pipe. I "seal" my two with hitemp silicone, make sure the engine mounting bolts are good and tight, esp the head steady, it doesn't take much movement to break the "seal". One of my bikes has a piece of thin copper sheet that I tap in the gap between the exhaust and the head, seems to help. Personally, I like a slight leak, the sucking in of air on the overrun followed by the inevitable glorious backfire really pisses of the neighbors.

"ignition" breaking down above 3,000 .... hmm ... more likely to be carburation, have you tried adjusting the needle down a slot? If you can stand it, 6,000rpm should be no real problem, though remarkable cruel.
Oil sump plate .......as I have said before .. there are two kind of Brit bike owners, those who's bikes leak oil and those that use silicone (SPAREINGLY!)

You take the head off and get the hole machined round again
Then you take your pipe to an exhaust shop that bends their ouw pipes and get them to expand yur pipe to be a tight fit

Second method is to fit spiggots into your head then split the end of the pipe and grind a little off the groove in the decorative collar so it becomes a proper clamp to clamp the pipe onto the spiggot .

Third method is to drill a hole in 2 fins to take a pawl / bolt and tack a hook onto to the pipe to take a spring to hold the pipe in

Fitting a less restrictive muffle also helps as does making sure the muffler mount and muffle clamp is tight

I have also seen bikes with a nut fitted either side of the pipe mounting bracket so it is fully restrained by the mounting stud in a position that has the pipe correctly fitting into the head .

+1 to everything mentioned.

I picked up a cheapo exhaust pipe expander and broke it the first time I tried it……..my fault, I thought you just stuck it In the pipe and cranked away.

Got a second one (I’m hardheaded) and this time took my time and tried to expand the pipe a “little” at a time. I say “little” because overall I couldn’t move the pipe much…..but it did finally work. Test fitting all along.

If you take it to a muffler shop you’d need to be sure you don’t go too big.

Lots of folks use a “shim” along with high temp sealer. Even with a “good” fit I still use a smear of sealer……just make sure you put it on the pipe…..not the head. Pretty much all that little cooling collar does for me is hide that ugly orange sealer.

With an okay fit (not perfect)…..the sealer lasts until I have to remove the pipe. If I’ve got a sloppier fit it might last a 1000 miles?

That popping on deceleration is a sure sign the sealer’s failing.

Like what’s been said already…….make sure everything involved with mounting is tight.

The best way to fix the exhaust pipe is buy an exhaust pipe expansion tool, new pipes dont have the same wall thickness as original pipes and tend to be a fraction smaller. Ive had orginal pipes been a reasonable fit in a port and new ones be somewhat "not". Flare it to the right size and you'll not need to bother with "goop" again!

I wouldn't mess about with carburation until you have fixed the header pipe.

Decent celulose gaskets and clean flat surfaces will cure the sump leaking problem. There is no reason why the bike should leak oil, certainly not with improved materials of today.

Sadly I cannot get your video to play.

So if I adjust the needle down a notch, that will move it towards a "lean" mix, correct? That I can do.

The head pipe sealing is mystifying me, since I thought the fit was pretty good. It's a new head pipe and sits against the head fully inserted. The muffler has no restriction, it's just empty.

I agree with all of the previous advice and my thoughts are as follows:-

- looking at the video, the silencer seems to wobble a bit when the bike is revved, so ensure it's tightly mounted to the bracket and also check that the down pipe is tightly clamped to the silencer. Any looseness of the exhaust & silencer won't help the seal, also worth checking the engine mounts and head steady are tight

- I use high temp silicone to seal the pipe in the head, it's best to assemble the parts and then let the sealant cure overnight, Loctite 5990 works well.

- To get the timing spot on you really need to check the static timing marks on the alternator rotor align with the pointer on the primary cover and then use a strobe to check the timing is advancing properly. Often a different rotor has been fitted and the marks don't align, so you have to use a dial gauge down the plug hole to find TDC and then turn the engine backward to find the full advance, the timing marks are then painted on the alternator rotor and strobed. Worth looking at one of the B44 owners manuals on the BSA Unit Singles spares website Here

- You don't mention what type of ignition is fitted, so it would be useful to know, both points and EI have their own different problems.

- The stutter at 3000k might be carb related, standard jetting for a 1968 B44 is 220 main, needle clip position 2.

- Max revs for a B44 is around 6500-7000k, any more and it feels like the engine is going to grenade.

- The leaking sump plate might be caused by loose or partially stripped studs. I like to remove the studs and fit helicoil thread inserts and then use socket cap screws to hold the sump plate on, this makes for a more robust fixing. Many owners like to change the sump plate for an alloy one which has a magnetic drain bolt and so helps keep the oil clean.

Thanks for the response Gunner.

The silencer and the head pipe have a spacer sleeve between them, and the fitment is pretty good, and tight. The issue is the back strap is long enough that it vibrates. I may need a second mount for that. The head pipe is rock solid. I will try the Loctite 5990.

I have tried using my timing light. If only I have another pair of eyes and hands. It's really hard to do that one by myself. Not many vintage bikers here in Ky. I do have it close and just ride around the block to test it. I'm doing both the B44 and a Puch SGS 250 at the same time, just timing and carburation left. The Puch has a really easy system for setting the fine timing with an eccentric on the points adjuster. The BSA does not. Also, other than the steel tank and clubman bars, and silencer, It's all original, So I'm using the points. I have a Boyer electronic I could use, but I'd rather stay with the points for now.

I have a new AMAL right from the factory, newly made, which is awesome. I will drop the needle, and see if that affects the high end break up. Has anyone ever tried tuning the carb with a tailpipe gas analyzer? Is that kinda nuts?

I have a service manual, I guess it's come to that point where I should read the directions.

Getting this to a high state of tune is pretty important to me right now. I may be thinning the heard in the spring, and the BSA seems like a contender to stay.

Oh what a difference a single word makes. When I said "needle down a slot", what I meant to say was "needle CLIP down a slot" i.e. rich it up a bit!

In my experience the AMAL carbs "direct from the factory" are pretty well set up and ready to go (so long as you ordered the right one!), so perhaps the issue is elsewhere. Do you have to have the idle / primary mix screw out a long way? i.e. to compensate for an air leak??

How good are your points / AR, are they bouncing around, .... advancing properly? points gap? condenser?....... springs get old......... "90% of Carbureta problems are the spark plug", especially if it is a new carb!

Agreed, whenever I've tried to strobe my B44 the bike jumps all over the garage when the engine is revved, so really helps to have someone else around.

If the carb is new and jetted somewhere around the settings I mentioned, then the problem may be with the ignition, so thats where I would be looking.

I'm not an expert with points and always use EI instead, but it sounds like either the static timing is too far retarded and so full advance isnt being reached or the static timing is correct but the AAU unit isnt advancing fully.

Have a look at an old thread about ignition timing B44's Here

This is my life in a nutshell. I thought I'd get it close enough and then examine the plugs to see if it's running rich or lean.

Gunner; I just looked yesterday for the Boyer and I can't find the thing now. I really wanted this to run on points, but thats not going to happen now.

The Boyer on a B44 makes life much easier. If it’s fitted with a choke, make sure that is off when running.