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Messages - Steve.S

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Sorry, the Pinion is 27-4106, not 4107.

I too retoothed my own sprocket several years ago. I found the sprocket was hardened, making the job very time consuming. The sprocket warped during welding, and again during the hardening process. Some say the sprocket doesn't need hardening, so you'll have to choose.
I used to send mine to John Hemmings Engineering, but I haven't been able to contact them lately.
I have found that Simon Bateman at Nametab Engineering (01527 60395) can retooth them, but they are very busy, and it will take several months.
I believe you need 27-4112 Kickstart Ratchet. These seem to be available from Draganfly at a cost of 10.01 excluding Value Added.
I would try Cornucopia for the Pinion 27-4107, but it might work with just a new Ratchet.
Good to see someone else also has a 1933 B2. Unfortunately they are a bit different to all the other years, having no cush drive and a Maglita driven by a thin bicycle chain at engine speed from the crankshaft. I found the chain broke regularly until I fitted a beefier wider chain.

Pre War / Re: 1934 Blue Star foot change gearbox selector lever 15-4137
« on: 26 September, 2022, 19:59:46 »
The lever is 1/4" thick. Distance between centres is 1 5/16". Square is 7/16"
If you place the square end of the lever on a surface plate, the distance between the surface plate and the underside of the hole end of lever should be 1/4" .
I hope this makes sense? I'm afraid I'm not intelligent enough to send photos.

Pre War / Re: 1934 500 Blue Star primary chaincase
« on: 29 August, 2022, 13:54:38 »
I don't know if it was a typo, but the only nut that is finger tight is the stepped nut against the spring, followed by the lockwasher and then the locknut, which should be reefed up very tightly.
The felt seal 15-270 fits over the clutch pushrod between the ratchet assembly and the outer cover. On the first gearbox I did, I assumed this felt fitted on the outside, like the Sloper and was very small, but whatever I did, I couldn't get it to stay in place. Silly me.
If you look on the WDM20 forum, in the technical section, you will find a very useful list of all the washers, felts etc. entitled 'Gearbox Identification'.
By the way, I also reduced length of the kickstart bush by about 1/8" (3.2mm in foreign currency) and fitted an O ring and a thin shim washer between the casing and the kickstart. Seems to work.

Pre War / Re: 1934 500 Blue Star primary chaincase
« on: 29 August, 2022, 02:48:24 »
I too did what I was told.
I think you will find that the cluster gear should be a very tight fit on the mainshaft. If you ever strip the gearbox again, you might want to assemble it with some Loctite. I don't know how important this is, but if it moved in use, could it contact the casing or perhaps alter the endfloat?

This is probably not relevant to you now, but I found that with a steel shielded bearing, when stationary, oil continuously dripped out until it was almost empty. Mind you, I mistakenly fitted the 2 oil retaining washers 24-4225 the wrong way round, which probably didn't help. I believe the inner one should be fitted so that there is a gap between the washer and the outer race, so oil can enter the bearing, and the outer should be fitted so that the outer diameter of the washer just contacts the outer race, and so tends to provide a seal. I found that, in practice, although the washer turns against the stationary outer race, it only rubs very lightly, and just tends to polish the outer race.

Assuming the washers have been fitted the right way round, it might be worth filling the gearbox with oil, to 1/2" below the top of the filler neck, and see if the oil comes out through the bearing. Oil came out of mine straight away, so, as you say, thixotropic oil may stop the leaks. Do you have to heat it to pour it in? I know Douglas used this oil, but they fitted a grease nipple and I gather you just pumped away until it started oozing out all over the place.

Anyhow, good luck with it all, and let us know what it's like on the road.

Pre War / Re: 1934 500 Blue Star primary chaincase
« on: 28 August, 2022, 20:22:41 »
 So that's how you got the mainshaft to move outwards!  There is also an oil flinger washer 24-4235 which sits between the distance washer and the gear cluster.. I found a distance washer that was 0.128" thick, and a Draganfly replacement was 0.118" thick. Selective assembly? The cluster should be an interference fit on the mainshaft, and will need a sturdy press to remove.
I had not mentioned the distance piece in my last post, but of course you must not assemble the gearbox without it. It would be disastrous, as you suggest, and give about 1/4" of mainshaft endfloat.
It is BSA who say that the ratchet nut should only be tightened finger tight. It is locked in place by the tab washer and locknut. Search for the M20 instruction manual.
If you've fitted a sealed main bearing, then I'm pretty sure the gearbox won't leak with 50 grade oil (mine didn't leak), but the choice is yours.

Now then, should you fit a sealed bearing to the inner cover? I haven't because I don't  want the kickstart to run dry.
I absolutely agree with you about GTX and Duckhams.

Singles / Re: Ignition Timing
« on: 28 August, 2022, 17:06:03 »
If it's not pinking then it's not too far advanced.
I wonder if you might try dropping the needle 1 notch? Or perhaps a hotter running plug to burn off the deposits?

Pre War / Re: 1934 500 Blue Star primary chaincase
« on: 28 August, 2022, 16:51:36 »
Many different opinions. Here's mine.
I don't understand how you can move the mainshaft out to the "correct" position. The splined register on the mainshaft  sits against the sleeve gear and the mainshaft cannot move further outwards. (Earlier gearboxes had a thrust washer here). The distance between the gearbox sprocket and the clutch sprocket is set, and cannot be altered except by machining, or perhaps a badly worn taper, or maybe you have the wrong clutch hub?
You must use a sealed main bearing. Use an LLU bearing, which is a contact sealed bearing, not a LLU bearing. Then you can use 50 grade oil as recommended, without leaks. Don't forget the felt washer on the clutch pushrod before you fit the outer cover.
It seems using a sliding plate will make your clearance problems worse. ( Not fitted on 1934 Blue Star).
I think you should firstly check sprocket alignments and work from there.
The Blue Star gearbox is essentially the same as the early M20 gearbox, (later ones had a completely different outer cover for enclosed footchange) and you must set mainshaft, layshaft and selector shaft endfloat for a good gearchange. Do not tighten the kickstart ratchet nut more than finger tight.
The inner cover gasket plays a part in setting endfloat, so I would not use silicone sealants etc.
There are many washers and spacers on the mainshaft, some of which are not shown on the M20 diagram.
I have read of people using Thixotropic grease for many thousands of miles without problems and I have also read of gearboxes seizing up solid within 50 miles. I don't know how quickly (or if) the grease becomes liquid, but it has to move through 1/8" holes to lubricate the bushes. I have found it's not that difficult to make these gearboxes reasonably oil tight.
My understanding is that back in the 50's EP oils attacked bronze, but they quickly resolved the problem.
Finally, I too had the problem of a warped inner case not clearing the sprockets, so I fitted it and used a stout screwdriver to lever it about until it cleared.
Hope some of this might help.

Pre War / Re: Oil pump to oil pipe connector for a pilgrim pump
« on: 31 July, 2022, 17:39:14 »
I thought the Blue Star has a gear pump under the engine driven by the half time pinion.
If it's a pilgrim pump, perhaps it's a B2? Anyhow, what I think you need is a 1/4 BSP to 1/4 BSP male adaptor. If you search on Ebay or Amazon, I think you will find one. Or try

Pre War / Re: New owner, first old bike - b21, issues!
« on: 12 July, 2022, 15:26:37 »
It's unusual for the needle to stick. More likely, it's the slide. This can be caused by overtightening the flange nuts, causing the body to distort.
I wonder if the slide is not bottoming on the slow running screw, perhaps the cable is holding the throttle open? Maybe give it a bit of free play?
You should be able to unscrew the slow running screw until the engine stops.
If you're sure the slide is bottoming, then another reason for a fast idle is an air leak. Spray WD40 over the flange with the engine running to check. Also spray grease on the inlet valve stem to check for leaks here. You may be able to grasp the valve collar with a pair of molegrips to check for play without dismantling.
I have found that laying the spark plug on the head doesn't tell you much. What you need is a spark gap tester. This is just an adjustable gap. I made one following the instructions in "The Motorcyclists Workshop", and it's saved me hours of grief. A reliable spark over a 3/16" gap indicates 8,000 volts, 1/4" gap 10,000 volts and 5/16" gap 15,000 volts. Don't go over 5/16" gap as you may damage the windings.
Have you tried screwing in the air screw to cure the spitting back?

Pre War / Re: B31-2 clutch spring adjustment
« on: 08 July, 2022, 16:18:49 »
I find it's trial and error. I screw the nut up until about 1 thread of the hub is showing, refit the dome and pushrod and try to kickstart the bike. If it slips, I screw it in another complete turn. I find that if it doesn't slip on the kickstart, it doesn't slip on the road. If a lot of effort is required to pull the lever in, and the clutch still slips, you may need to boil the friction discs in detergent, especially the one behind the chainwheel, which gets covered in oil with use. Maybe fit new friction discs. Hope this helps.

Pre War / Re: 1934 Blue Star fork assembly
« on: 12 June, 2022, 16:27:33 »
I completely agree with Alan G. I can also confirm that both Percival Brothers and Webb, and Jake Robbins don't use these washers, just flat washers. If BSA were concerned about the nut coming loose, I think a single spring washer would have been more effective here than a thackery washer. I have never known these nuts to come loose  (just using a flat washer). It wouldn't surprise me if BSA had mistakenly ordered thousands of thackery washers, and had to use them up somehow. The only place I use them, is under the steering damper knob.

Pre War / Re: Valve rocker shaft
« on: 12 June, 2022, 15:54:32 »
I am sure the rotational position of the rocker shafts is not important., but it looks more professional if they are in the same plane.

Pre War / Re: New owner, first old bike - b21, issues!
« on: 12 June, 2022, 15:41:36 »
Is there any debris in the float bowl? I see you have already had a new float needle fitted, and have ordered another one. Part no. AM/14/024. Assuming it's a bottom feed float bowl, you should be able to unscrew and remove the cover, turn the petrol on and it shouldn't overflow. If it does, the needle is not seating. Remove the float bowl, turn it upside down and examine the seating closely. Check for dead flies etc. You may need to lightly polish the needle and seating with a little brass polish. If you disturb the Union Nut which screws onto the bottom of the carburettor body, be careful not to over tighten it, otherwise the bottom of the carburettor will break off. I understand the new needles have 2 grooves. The top groove is for copper floats, and the bottom groove is for plastic floats. Assuming yours has only one groove, and a copper float, the float height is non adjustable, but with the cover off, you will be able to see where the petrol level is. I think the petrol level should be just below the the top of the needle jet. Make sure that both tangs of the float clip stay in the groove. Often the top one springs out. Bend as required.
You may need to fit an inline fuel filter to stop debris getting into the float chamber. Also, check that the small horizontal breather hole in the knurled part of the cover is not blocked.
I would fit an inline tap in your oil feed line. You can buy one with a switch which earths the magneto when in the off position.

Pre War / Re: Bsa b1 1933 first bike need help
« on: 12 June, 2022, 14:54:46 »
It's a bit late, but you need spring 27-4170. Try Cornucopia in Germany. In the meantime, you could tie a bungee strap around the kickstart lever.

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