Search found 1637 matches

by kommando
Tue Jun 04, 2019 2:34 pm
Forum: Tech
Topic: Bsa b40g engine tuning
Replies: 19
Views: 924
Flag: Ireland

Re: Bsa b40g engine tuning

My Bad, 7/16th BSF in B40G pre 69 cases as they do not have raised number stamp pad, 69 B44 cases 7/16th UNC.
by kommando
Mon Jun 03, 2019 8:03 pm
Forum: Tech
Topic: B25/B44 wiring
Replies: 14
Views: 3686
Flag: Ireland

Re: B25/B44 wiring

Not sure how, I know my Wassell rectifier/regulator leaks to earth and discharges the battery on my Commando with the ignition off but that's because it's crap and I have a replacement not because the wiring is defective.

Image
by kommando
Mon Jun 03, 2019 10:42 am
Forum: Tech
Topic: Bsa b40g engine tuning
Replies: 19
Views: 924
Flag: Ireland

Re: Bsa b40g engine tuning

Assuming you are talking about the case end of the stud.

Neither, 7/16 Whit, B44 started as 7/16 Whit and then went to 7/16 UNC which has the same TPI, so just a change of thread angle.

But check first in case a DPO has messed about.
by kommando
Thu May 30, 2019 10:12 am
Forum: Tech
Topic: B44 Alternator Repair
Replies: 7
Views: 251
Flag: Ireland

Re: B44 Alternator Repair

It goes in the bucket and you buy a replacement. I can't find the book but from memory Rupert Ratio's fix is not for a rotor that's disintegrating but for a rotor loose on the soft B25 crank mainshaft. Its soft as the big end is a shell bearing and the crank is not hardened, the built up cranks have...
by kommando
Wed May 29, 2019 4:19 pm
Forum: Tech
Topic: b25ss timing cover bung plug/past shortage of B50 kickstart quadrants
Replies: 17
Views: 406
Flag: Ireland

Re: past shortage of B50 kickstart quadrants

Could we have only one version of this post not 2 ?

Edit by MM: Your wish is my kommando
by kommando
Wed May 29, 2019 4:17 pm
Forum: Tech
Topic: b25ss timing cover bung plug/past shortage of B50 kickstart quadrants
Replies: 17
Views: 406
Flag: Ireland

Re: b25ss timing cover bung plug

You know the B40 one fits but is worn, so send the B50 one back and ask for it to be replaced by a B40 one (which should be the same as the B44 one and middle run of production of B25, the early B25 may have a thinner kickstart shaft, the early B40 one did). The key way was not on genuine BSA kickst...
by kommando
Wed May 29, 2019 8:05 am
Forum: Tech
Topic: b25ss timing cover bung plug/past shortage of B50 kickstart quadrants
Replies: 17
Views: 406
Flag: Ireland

Re: b25ss timing cover bung plug

Steve's mentioned it first ;) , it is the oil level plug but not sure it's set at the normal level as going by the factory literature the gearbox capacity was larger for the WDB40G. Maybe they distrusted the squadrons checking the level often enough and so increased the oil level to be safe.
by kommando
Tue May 28, 2019 5:24 pm
Forum: Tech
Topic: b25ss timing cover bung plug/past shortage of B50 kickstart quadrants
Replies: 17
Views: 406
Flag: Ireland

Re: b25ss timing cover bung plug

WDB40G standard fitment but just not as large a nut, note these WD engines were being still made into 71 so who knows if its a Previous owners mod or some WDB40G outer timing cover was fitted when the std ones ran out on the line.
by kommando
Wed May 22, 2019 5:43 am
Forum: Tech
Topic: c15c - B44 type frame
Replies: 19
Views: 833
Flag: Ireland

Re: c15c - B44 type frame

My question from here is how similar is the works frame to a production frame and am i able to make a convincing works frame clone out of a production frame. The works was OIF yes but it was a C15 comp frame as the changes were very small to make it OIF, it used the top tube but had a small header ...
by kommando
Mon May 20, 2019 2:44 pm
Forum: Tech
Topic: c15c - B44 type frame
Replies: 19
Views: 833
Flag: Ireland

Re: c15c - B44 type frame

I have heard mention that the C15C frame was based on a works frame so i will look for reference to the works bike to see how similar it really is. You need to find out about 'Black Bess', works bike for Jeff Smith, started as a 350, went to 420, then 441. It used the works frame which became the C...
by kommando
Tue May 14, 2019 10:51 am
Forum: Tech
Topic: Bsa b40g engine tuning
Replies: 19
Views: 924
Flag: Ireland

Re: Bsa b40g engine tuning

Do not grind down the follower foot, the early ones are weak and BSA made them thicker to compensate, do not go back the way. Shorten the cam follower tunnel to the B44 size instead and check its enough before finishing the cut. 1- get a set of double diameter studs made up to suit? 2- sleeve the ba...
by kommando
Thu May 02, 2019 1:30 pm
Forum: Tech
Topic: Truckle slide
Replies: 20
Views: 1520
Flag: Ireland

Re: Truckle slide

It looks like a tiny "mouse hole" in the bottom of the port side of the slide. Where does the radius of the carb throat come into it? Thanks. First attempt was the mousehole but dropped instead for hole with radius of carb throat. On my 250 and 441 I do not get this small opening issue, wonder what...
by kommando
Tue Apr 30, 2019 10:21 am
Forum: Tech
Topic: B50 doesn't like tickling
Replies: 6
Views: 308
Flag: Ireland

Re: B50 doesn't like tickling

The correct tuning for a pilot jet is to get the bike fully warm and then tune the pilot air mixture screw for highest revs, then lower the revs and redo the tuning just in case lowering the slide alters the mixture. That should result in the mixture being too lean on a cold engine and hence the nee...
by kommando
Mon Apr 29, 2019 5:38 pm
Forum: Tech
Topic: Kick-start aid
Replies: 8
Views: 389
Flag: Ireland

Re: Kick-start aid

You can sort out the 850 MK3 starter. 1. Thicker cables 2. Heavy duty solenoid 3. 4 pole conversion to starter 4. High CCA battery If you have EI which over advances when the voltage drops then add a voltage buck in series, 5A capacity should do it, and this will retain 12V at the Boyer until the ba...
by kommando
Fri Apr 26, 2019 6:25 pm
Forum: Tech
Topic: Head Gasket Fitting - tips and tricks.
Replies: 6
Views: 355
Flag: Ireland

Re: Head Gasket Fitting - tips and tricks.

The B44 correct head gasket is the same thickness as the B40, the pattern B44 is made too thin but if its the correct thickness it also fits the B40. The pattern one is also too thin for the B44.
by kommando
Tue Apr 23, 2019 4:55 pm
Forum: Tech
Topic: 1000-Series 2/4-stroke Concentrics
Replies: 84
Views: 2548
Flag: Ireland

Re: 1000-Series 2/4-stroke Concentrics

Its ok through the full range as long as there is no load on the engine, so that negates a lot of the info it gives from mid throttle upwards as you need a load 1/2 throttle onwards. So its perfect for idle, gives you good info on the transition from idle to throttle cutaway and then starts to give ...
by kommando
Wed Apr 17, 2019 12:23 pm
Forum: Tech
Topic: In search of reliable B25 oil pressure.
Replies: 74
Views: 9830
Flag: Ireland

Re: In search of reliable B25 oil pressure.

Too much money compared to a refresh of a pump.
by kommando
Wed Apr 17, 2019 12:02 pm
Forum: Tech
Topic: In search of reliable B25 oil pressure.
Replies: 74
Views: 9830
Flag: Ireland

Re: In search of reliable B25 oil pressure.

On Norton pumps the shaft leak is fixed by fitting O rings to the body where the shafts run. Should be easy enough to replicate on a Unit Single pump.

Here is a Norton one I did but substituted X rings.

Image

You need a vertical mill to do it properly.
by kommando
Wed Apr 17, 2019 8:46 am
Forum: Tech
Topic: In search of reliable B25 oil pressure.
Replies: 74
Views: 9830
Flag: Ireland

Re: In search of reliable B25 oil pressure.

Your pump is leaking from the feedside to the scavenge side through the shafts and both non return valves are not working.
by kommando
Wed Apr 17, 2019 8:44 am
Forum: Tech
Topic: Bsa b40g engine tuning
Replies: 19
Views: 924
Flag: Ireland

Re: Bsa b40g engine tuning

I do understand that taking material from the bottom does weaken the base and the barrel is thinnest in the middle etc.
The bottom is the strongest and the amount you will be taking off will not weaken it at all.
by kommando
Tue Apr 16, 2019 6:05 pm
Forum: Tech
Topic: Bsa b40g engine tuning
Replies: 19
Views: 924
Flag: Ireland

Re: Bsa b40g engine tuning

Its a B40G Jeff, so its B25/B44 crankcases slightly modified for the low lift cam, no distributor and other than wide ratio gearset the gearbox is already B25/B44. Not many in US but a lot in Europe as the Military used them. They were being built until 71 at least with all the changes except for th...
by kommando
Tue Apr 16, 2019 11:10 am
Forum: Tech
Topic: Bsa b40g engine tuning
Replies: 19
Views: 924
Flag: Ireland

Re: Bsa b40g engine tuning

1. 20mm longer stroke means 10mm higher and then adjusted for any changes in piston height, B44 is 9.4:1 but B40 9:1 is available and the extra .4 can be adjusted in. 2. MX cam in a short stroke high revving engine may not be the right way to go, MX will give better low down grunt but not much up to...
by kommando
Sun Apr 14, 2019 12:50 pm
Forum: Tech
Topic: In search of reliable B25 oil pressure.
Replies: 74
Views: 9830
Flag: Ireland

Re: In search of reliable B25 oil pressure.

What is the oil level in the frame, if its too high and has reached the return pipe outlet then it will siphon the excess oil out. Or someone has added a longer tube to G to stop the returning oil from short circuiting to the oil outlet and its too long and is below the oil level. http://b50.org/rno...
by kommando
Sat Apr 13, 2019 3:31 pm
Forum: Tech
Topic: In search of reliable B25 oil pressure.
Replies: 74
Views: 9830
Flag: Ireland

Re: In search of reliable B25 oil pressure.

The scavenge non return in the sump drain only holds back the oil in the pipe, nothing more and just keeps the pump scavenge gears full of oil, the feedside non return in the inner timing cover stops the oil tank contents from draining into the engine when it not running.
by kommando
Sat Apr 13, 2019 10:16 am
Forum: Tech
Topic: In search of reliable B25 oil pressure.
Replies: 74
Views: 9830
Flag: Ireland

Re: In search of reliable B25 oil pressure.

New ball and spring are mandatory every time you maintain that non return valve, the ball gets a set for the seat and the seat distorts and spring loses tension. Even with a new ball, tapping it onto the seat and new spring will not fully work but at least slows it down. The relief valve is after th...
by kommando
Fri Apr 12, 2019 9:59 am
Forum: Parts & Bikes wanted
Topic: Bsa b44 round barrel and head
Replies: 1
Views: 424
Flag: Ireland

Re: Bsa b44 round barrel and head

A B40 90SS head with the 4 barrel stud holes opened up to suit the B44 studs is the same as a B44 round barrel head and is how I got mine sorted.
by kommando
Fri Apr 12, 2019 9:10 am
Forum: Project bikes
Topic: B25ss Goldstar.
Replies: 5
Views: 498
Flag: Ireland

Re: B25ss Goldstar.

Not an expert at all, just looking for ways to cope with our potholed roads and came across digressive damping which both promised and delivers if tuned correctly. I have CBR600RR Showa cartridges with shim stacks in my Commando so knew it worked but then found if you fitted them to OIF then you end...
by kommando
Thu Apr 11, 2019 4:49 pm
Forum: Project bikes
Topic: B25ss Goldstar.
Replies: 5
Views: 498
Flag: Ireland

Re: B25ss Goldstar.

Lathejack if you need any info on my BMW SS1000R insert re-engineer KK has added the link to then ask here or PM me. For someone with a lathe and mill its not hard to do especially based on what pics you have posted, beats my turning attempts. As the cartridge inserts are upgraded as soon as the bik...
by kommando
Thu Apr 11, 2019 4:10 pm
Forum: Tech
Topic: Bsa b40g engine tuning
Replies: 19
Views: 924
Flag: Ireland

Re: Bsa b40g engine tuning

The B40G has a low lift camshaft short duration cam as fitted to the C15 B40 standard models with sometimes the B40 valve head but later some seem to have got the B40 90SS larger valve head. The carb is also restrictive and it has a low compression piston. You have a few options to pick from or you ...
by kommando
Tue Apr 09, 2019 8:45 pm
Forum: Tech
Topic: 1000-Series 2/4-stroke Concentrics
Replies: 84
Views: 2548
Flag: Ireland

Re: 1000-Series 2/4-stroke Concentrics

But all 850's have the slotted spray tube, so the 260 was on a slotted spray tube carb but comparing to 230 or 200 tells you nothing as they had slotted too. Unless you test 850 carbs with unslotted spray tubes to find the best main jet and the change to slotted and see if any change is needed only ...
by kommando
Tue Apr 09, 2019 1:39 pm
Forum: Tech
Topic: 1000-Series 2/4-stroke Concentrics
Replies: 84
Views: 2548
Flag: Ireland

Re: 1000-Series 2/4-stroke Concentrics

As fitting the 200 jet could cause engine blow-up/seizure I have to reference the 200 as being fat fingers at Amal and it has been covered before. https://www.accessnorton.com/NortonCommando/amal-premiers.27334/page-2#post-412163 200 according to Amal's information, 230 according to the Mk3 manual a...
by kommando
Mon Apr 08, 2019 7:47 pm
Forum: Tech
Topic: 1000-Series 2/4-stroke Concentrics
Replies: 84
Views: 2548
Flag: Ireland

Re: 1000-Series 2/4-stroke Concentrics

Since the 200 was fitted only for that one year and for that one model, what was different about it? Different cam? Different gearing (so engine was at a different rpm at the road speed of the roll-on test)? Other? I can find no reference to a 200 main jet on the mark 3 in handbooks, workshop manua...
by kommando
Mon Apr 08, 2019 5:00 pm
Forum: Tech
Topic: 1000-Series 2/4-stroke Concentrics
Replies: 84
Views: 2548
Flag: Ireland

Re: 1000-Series 2/4-stroke Concentrics

And a smaller main jet. The 1973 Roadster used a 260 while the 1974 MkIII Roadster used a significantly smaller 200. Not quite as simple, I have the MK2a which was the same air cleaner and black cap silencers as the MK3. When you change the black cap silencers for the unmuted peashooters you have t...
by kommando
Mon Apr 08, 2019 2:50 pm
Forum: Tech
Topic: 1000-Series 2/4-stroke Concentrics
Replies: 84
Views: 2548
Flag: Ireland

Re: 1000-Series 2/4-stroke Concentrics

It was the first 850, the silencer was the peashooter fitted with mutes in the end of the silencer exit. Odd that they mixed a richer spray tube with a longer weaker needle to cure a mid range richness.
by kommando
Sat Apr 06, 2019 12:09 pm
Forum: Tech
Topic: 1000-Series 2/4-stroke Concentrics
Replies: 84
Views: 2548
Flag: Ireland

Re: 1000-Series 2/4-stroke Concentrics

No idea on the slanted spray tube but the story behind the stepped 850 Commando one suggests the stepped one enrichens the mixture as it was to cure a flat spot at low revs and a snapped open full throttle. John Healy seems to agree http://vintagebikemagazine.com/technical-articles/amal/ Too Lean Co...
by kommando
Fri Apr 05, 2019 10:30 pm
Forum: Tech
Topic: Imperial thread sizes
Replies: 16
Views: 554
Flag: Ireland

Re: Imperial thread sizes

I know the difference in the specs, just can't see any maker being bothered. 1/4 fasteners are not critical, prefer to take the time to get the right crank nuts.
by kommando
Fri Apr 05, 2019 4:55 pm
Forum: Tech
Topic: Imperial thread sizes
Replies: 16
Views: 554
Flag: Ireland

Re: Imperial thread sizes

Do like me and don't bother, I treat them as being the same, suspect most suppliers of taps and dies do not bother either and all are BSF with some labelled Cycle. If I ever come across a critical 1/4 nut or bolt application I will bother but never come across one.
by kommando
Wed Apr 03, 2019 8:07 am
Forum: Tech
Topic: B44 Inner Timing Cover Damage and Differences
Replies: 6
Views: 400
Flag: Ireland

Re: B44 Inner Timing Cover Damage and Differences

There will be differences, only close examination will tell you what they are and if they matter. I would try to keep original as they were machined as matched sets with the cases and some will give issues with mismatches on shaft hole positions.
by kommando
Fri Mar 29, 2019 10:20 pm
Forum: Tech
Topic: B44 Crank Ball Bearing - Sludge trap removal
Replies: 15
Views: 811
Flag: Ireland

Re: B44 Crank Ball Bearing - Sludge trap removal

Yes, 65 or 64 model year.
by kommando
Fri Mar 29, 2019 3:38 pm
Forum: Tech
Topic: B44 Crank Ball Bearing - Sludge trap removal
Replies: 15
Views: 811
Flag: Ireland

Re: B44 Crank Ball Bearing - Sludge trap removal

Which is still not right as the B40F and C15F have sidepoints with a blocked off distributor hole and no distributor but still the same arrangement as the distributor models.

Oblong sump cover vs Square sump cover is foolproof.