Search found 766 matches
- Tue Feb 02, 2021 10:07 pm
- Forum: Tech
- Topic: B50 hydraulic drum brake
- Replies: 53
- Views: 2920
Re: B50 hydraulic drum brake
What makes you thing that the forces from an hydraulic brake are any higher than the forced from a (working) mechanical brake? The forces expanding the shoes will be the same for the same amount of braking but the hydraulic brake won't have the additional forces from the operation of the cam mechan...
- Sun Jan 31, 2021 7:46 pm
- Forum: Project bikes
- Topic: B50/44 Hybrid
- Replies: 28
- Views: 2125
Re: B50/44 Hybrid
I once fitted a B40GB engine into a B25 OIF frame and this is what I found I needed to do:- - the frame was cleaned internally by using various combinations of hot soapy water, paraffin, paint thinners, engine degreaser, pressure washer etc. Each time I filed the frame it was vigorously shaken aroun...
- Sun Jan 31, 2021 5:09 pm
- Forum: Tech
- Topic: B50 hydraulic drum brake
- Replies: 53
- Views: 2920
Re: B50 hydraulic drum brake
Great conversion, my only worry would be the strength of the brake plate and whether it can withstand the additional forces added by the hydraulics. I only say this because I once sold a B25 OIF brake plate on eBay, when it arrived it was broken in half, presumably due to poor handling by the courie...
- Mon Jan 04, 2021 2:17 pm
- Forum: Tech
- Topic: b40 lubrication system modification ?
- Replies: 15
- Views: 972
Re: b40 lubrication system modification ?
ive read somewhere theres a conversion/modification to the lubrication system to make it more oil tight/breath easier/ lube more efficiently I suspect the mod you mean is the B50 conversion where two 3/8 holes are drilled in the crankcase drive side, just under the crankshaft and level with what wo...
- Tue Dec 22, 2020 10:16 pm
- Forum: News
- Topic: Stan Millard
- Replies: 20
- Views: 2991
Re: Stan Millard
So sad to hear this news about Stan, I've learned much from his posts over the years on this forum, no doubt his expertise and knowledge will be missed by those seeking to improve their B44's & B50's.
- Sat Jul 11, 2020 12:33 am
- Forum: Tech
- Topic: B25SS Rocker Box Studs
- Replies: 10
- Views: 1716
Re: B25SS Rocker Box Studs
If it was my bike I would remove the studs, run a flat file over the rocker cover surface, then helicoil all the stud holes with a suitable thread form (I used m6 on my B44) and replace with socket caps. The two bolts holding the head steady are probably strong enough and can be left alone. But its ...
- Thu Jul 02, 2020 11:26 pm
- Forum: Tech
- Topic: Refurbishment of B25 cylinder head and rocker box
- Replies: 5
- Views: 1268
Re: Refurbishment of B25 cylinder head and rocker box
I can see several issues which you might want to address as follows:- - the valve seats look slightly pitted, I would get them re-cut ideally using a 3 angle valve job which helps efficiency, get the valves refaced at the same time - there is evidence of burnt oil on the inlet valve stem, this proba...
- Wed Jun 24, 2020 9:46 pm
- Forum: Tech
- Topic: 441 Victor resurection
- Replies: 45
- Views: 6665
Re: 441 Victor resurection
I'm using a JRC 28 carb on my B44 and it works well, one advantage is that it has a separate choke circuit so starting is a bit easier. I'm wondering if your Amal 930 has a blocked idle circuit, which as you probably know is a common problem, so may be worth cleaning out. Also worth checking the thr...
- Sun Jun 14, 2020 8:07 pm
- Forum: Tech
- Topic: B44 engineering item and a Piston recommendations?
- Replies: 6
- Views: 1627
Re: B44 engineering item and a Piston recommendations?
Back in the 70's and 80's a company called Basset Down near Newbury advertised their crank balancing services in the motorcycle press, not exactly near Cornwall but maybe worth a shot. Their website says they can balance any crank including single cylinder and they mention engine rebuilds on their w...
- Thu Apr 30, 2020 2:30 pm
- Forum: Tech
- Topic: Which tank sealant?
- Replies: 16
- Views: 4734
Re: Which tank sealant?
Not sure what sealant you have in the tank but I've previously had good success with Acetone for removing very old Petseal used in my A65 fibreglass tank. Acetone sloshed around causes the Petseal to flake off the inside in big chunks which can then be further broken down by adding old screws/nuts/d...
- Mon Apr 20, 2020 11:19 am
- Forum: Project bikes
- Topic: Converting a B50 to wet sump. (aka Boris Johnson)
- Replies: 102
- Views: 16812
Re: Converting a B50 to wet sump.
Some pics would be great :)
- Sat Apr 18, 2020 10:00 pm
- Forum: Project bikes
- Topic: Converting a B50 to wet sump. (aka Boris Johnson)
- Replies: 102
- Views: 16812
Re: Converting a B50 to wet sump.
Hi Momus, for many years I've wondered whether a unit single BSA could be converted from dry sump to wet sump so I think it's great that you're having a go at it. I imagine there are several obstacles to overcome when making such a radical change to the lube system:- - a new oil tank will need fabri...
- Tue Mar 24, 2020 7:19 pm
- Forum: Tech
- Topic: b44 gearbox leak/level
- Replies: 15
- Views: 2824
Re: b44 gearbox leak/level
i filled to the correct level (1/2 pint aqf ) Are you using ATF oil or gear oil? I use EP90 gear oil which is probably thicker than ATF with less tendency to leak out so is recommended. I'm using a level tube on my B44 without a dipstick and it seems to work OK, I dont know if this was the original...
- Mon Mar 23, 2020 2:27 pm
- Forum: Tech
- Topic: b44 gearbox leak/level
- Replies: 15
- Views: 2824
Re: b44 gearbox leak/level
I would change the gearbox output bearing to one with rubber seals, these are prefilled with grease and don't need gearbox oil. If youre worried about lack of lube you can remove the inner seal but keep the bearing outer seal.
- Mon Jan 27, 2020 11:57 pm
- Forum: Tech
- Topic: B40 in OIF frame issues
- Replies: 35
- Views: 6835
Re: B40 in OIF frame issues
Have a look at this thread where someone had a similar problem and solved it - viewtopic.php?t=4223
- Sun Jan 26, 2020 3:11 pm
- Forum: Tech
- Topic: B40 in OIF frame issues
- Replies: 35
- Views: 6835
Re: B40 in OIF frame issues
Regarding the knocking, check you engine mountings are tight, particularly the rear mount which has a habit of becoming oval in the engine cases. Make sure the head steady is fitted.
- Fri Jan 24, 2020 5:27 pm
- Forum: Tech
- Topic: B44 Primary Breather Pipe
- Replies: 8
- Views: 2320
Re: B44 Primary Breather Pipe
I've done the conversion on my B44 but without adding the external hose from the chain-case. My thinking was that allowing the crankcase to breathe into the chain-case would relieve some of the excess pressure and reduce leaks, it seems to work OK. For my conversion I drilled two 3/8 holes into the ...
- Mon Jan 13, 2020 8:29 am
- Forum: Tech
- Topic: B44 Wiring/ Earth
- Replies: 16
- Views: 3328
Re: B44 Wiring/ Earth
When making the loom, I've found heat shrink butt connectors very handy when a piece of cable needs extending. These items are essentially a piece of clear heat shrink tube with a ring of solder in the middle. Cable is inserted from either end and then the butt connector is heated with a hot air gun...
- Sun Jan 12, 2020 11:29 pm
- Forum: Tech
- Topic: B44 Wiring/ Earth
- Replies: 16
- Views: 3328
Re: B44 Wiring/ Earth
I have wired my B44 as positive earth as per original, I don't see any advantage in changing to negative earth. Make sure you use the right gauge cable, with a 180w alternator putting out up to 15 amps cable with inner core of 1mm square should be about right. Regarding the connectors I have no expe...
- Sat Dec 28, 2019 8:59 pm
- Forum: Tech
- Topic: B40 in OIF frame issues
- Replies: 35
- Views: 6835
Re: B40 in OIF frame issues
Oil is coming out of the joint between the head and exhaust downpipe, which is a concern. I had a similar issue with my B44 when I first put it together, I found oil coming out from the exhaust manifold where the pipe fits in, also plenty of blue smoke and some leaks from the head gasket area. Afte...
- Tue Dec 24, 2019 10:22 pm
- Forum: Tech
- Topic: B40 in OIF frame issues
- Replies: 35
- Views: 6835
Re: B40 in OIF frame issues
I once owned a similar bike, it was a B40WD engine in a B25 frame. As noted the carb doesn't fit very well without fouling the frame so what I did was to have an alloy inlet welded onto the head, I don't remember which way it was angled but it didn't use the original air filter. I was using a Dellor...
- Mon Dec 16, 2019 7:52 pm
- Forum: Tech
- Topic: B44 - 2nd Gear Mystery
- Replies: 6
- Views: 2034
Re: B44 - 2nd Gear Mystery
Could be a number of things affecting the gear change, in addition to Kommando's advice I would have a look at the Post Here which describes and fixes a similar problem to yours.
- Mon Dec 09, 2019 9:15 pm
- Forum: Tech
- Topic: Fitting Allen screws to rocker box on B50.
- Replies: 35
- Views: 7216
Re: Fitting Allen screws to rocker box on B50.
At the risk of sounding like a heretic, I've used M6 thread inserts on my B44 rocker-box together with socket caps. I think my main reason at the time was that M6 thread inserts were readily available, cheap and were only slightly different in TPI compared to the BSC/CEI originals (25.4 vs 26). I do...
- Wed Jul 03, 2019 9:36 pm
- Forum: Tech
- Topic: B40 and B44 motor in OIF chassis
- Replies: 7
- Views: 3363
Re: B40 and B44 motor in OIF chassis
I once fitted a WD B40 engine into an OIF B25 frame, my thoughts are as follows:- - the rear engine mount needs spacers fitting as already mentioned - the frame cross member will foul the oil manifold as Kommando mentions, easiest solution is to cut out the cross member, it doesn't affect the frame ...
- Sun Jun 09, 2019 8:22 pm
- Forum: Tech
- Topic: 1000-Series 2/4-stroke Concentrics
- Replies: 102
- Views: 24635
Re: 1000-Series 2/4-stroke Concentrics
Fantastic work MM and thanks for sharing this info which may be of some use on my B44 which currently uses a JRC 28 (Kehin PWK replica). I've often wondered about getting more performance from my B44 including gas flowing, bigger valves & carb etc. and why the unit single BSA's couldn't quite get th...
- Sat Jun 08, 2019 1:12 pm
- Forum: Tech
- Topic: b25ss timing cover bung plug/past shortage of B50 kickstart quadrants
- Replies: 17
- Views: 5142
Re: b25ss timing cover bung plug/past shortage of B50 kickstart quadrants
Regarding the plug on the outer gearbox/timing cover, its definitely meant to be an oil filler/level plug for a B40WD. Have a look at the B40WD workshop manual on the BSA unit Singles website Here plate A10. There's also a handy B40WD parts list Here which shows the plug on plate A11 part 20 which i...
- Sun May 12, 2019 10:35 pm
- Forum: Tech
- Topic: Dodgy clutch springs?
- Replies: 2
- Views: 1982
Re: Dodgy clutch springs?
IMHO the best way to ensure the springs and screws don't come undone is to use lock wire, don't rely on the pip or the springs being wound the right way, they invariably come loose unless lock wired in place.
- Wed Feb 20, 2019 11:56 am
- Forum: Tech
- Topic: Electric Start
- Replies: 635
- Views: 180139
Re: Electric Start
Well done Beat, great to see you have finally got it working :)
- Tue Jan 15, 2019 8:23 pm
- Forum: Tech
- Topic: B44 Oil consumption
- Replies: 29
- Views: 6408
Re: B44 Oil consumption
I had exactly the same problem when I rebuilt my B44 several years ago using a JCC piston and iron rings. The bike would smoke loads on startup and when warmed up despite a hard run-in process and a coarse hone. I swapped the rings for Hepolite versions and a fresh hone but the problem persisted. Ev...
- Mon Dec 17, 2018 11:30 pm
- Forum: Tech
- Topic: B50s and modern fuel
- Replies: 28
- Views: 8330
Re: B50s and modern fuel
If you cant get the Esso ethanol free unleaded in your area then one possibility is to use Briggs and Stratton fuel stabiliser which claims to keep fuel fresh for up to 3 years. Admitedley its meant for lawnmowers but I cant see it doing much harm in our old nails, see This Link.
- Fri Dec 07, 2018 11:08 pm
- Forum: Tech
- Topic: Chainguard?
- Replies: 4
- Views: 2041
Re: Chainguard?
Dont know if this helps but looking on eBay there is a B40WD enclosed chainguard and a B40/B44 chainguard available:-- - the first one is for a B40WD its the fully enclosed version, it seems original enough, maybe you could just loose the lower section if you dont want fully a enclosed chaincase, se...
- Sun Dec 02, 2018 10:09 pm
- Forum: Tech
- Topic: B50s and modern fuel
- Replies: 28
- Views: 8330
Re: B50s and modern fuel
This does not apply to Scotland or the South West where there are no reliably ethanol free petrol of any description. I can't imagine why Esso would have different formulations for Scotland and the South West, but perhaps its related to the capabilities of refineries in these areas? I guess you wil...
- Sun Dec 02, 2018 10:55 am
- Forum: Tech
- Topic: B50s and modern fuel
- Replies: 28
- Views: 8330
Re: B50s and modern fuel
Thanks for that info, luckily I have at least 6 Esso stations nearby which stock super unleaded and they all seem to be busy with customers. My guess is that the super unleaded is used alot so should be fresh in the tanks.The problem is that it does not have that big a demand so it can get old
- Sat Dec 01, 2018 8:05 pm
- Forum: Tech
- Topic: B50s and modern fuel
- Replies: 28
- Views: 8330
Re: B50s and modern fuel
From my research only Esso super unleaded (97RON) has no ethanol That's a top tip and the lack of ethanol is confirmed on the Esso UK website, see This Link , they also have a UK petrol station locator so you can find your local outlet. I'm going to fill my bikes with Esso super unleaded and see ho...
- Fri May 25, 2018 9:45 pm
- Forum: Tech
- Topic: Vent pressure from inside B40
- Replies: 20
- Views: 5440
Re: Vent pressure from inside B40
Some worthwhile fixes I have tried on unit singles to cure rocker box and cylinder stud leaks are as follows:- - countersink the rocker box stud holes on the cylinder head to remove any 'pulled up' metal, this will help ensure the rocker box flange on the head is reasonably flat and help prevent lea...
Re: New rings
I'm using Cords rings on my B44 and can recommend them, see This Link for the original post.
- Fri Dec 01, 2017 9:07 pm
- Forum: Tech
- Topic: Accelerator pump carb
- Replies: 27
- Views: 6996
Re: Accelerator pump carb
Good question B44Claus and as an owner many years ago of a Ducati Darmah 900cc Bevel drive which used Dellorto PHF carbs with accelerator pumps, I often wondered whether these carbs would be useful on other bikes. If I remember correctly, the purpose of accelerator pumps is to enrich the mixture whe...
- Mon Oct 16, 2017 8:42 pm
- Forum: Tech
- Topic: B50 MX sudden death!
- Replies: 41
- Views: 12249
Re: B50 MX sudden death!
Some thoughts which might be of use:- - have you checked the gearbox oil level? Its common for the gear box oil to slowly leak out as well as emulsify into a brown sludge, hindering lubrication - the engine and chain-case share the same oil so although there are traces of silver in the oil, if youre...
- Sat Sep 16, 2017 9:45 pm
- Forum: Tech
- Topic: Another valve guide question
- Replies: 20
- Views: 5542
Re: Another valve guide question
I have never tried the K-Line guide insert system but it looks like a good idea and I agree that its best to keep valve guides in place since removing them causes wear in the head. One of the motorcycle head specialists who offers this service in the UK is the Cylinder Head Shop, see This Link , so ...
- Sat Jul 22, 2017 10:03 pm
- Forum: Tech
- Topic: B50 starting niggle
- Replies: 18
- Views: 6029
Re: B50 starting niggle
Try using a tank of fresh petrol, cleaning out the carb bowl and idle circuit, which is notorious for becoming clogged.
Additionally try a fresh plug and make sure the battery is showing at least 12.5v which is essential if using electronic ignition.
Additionally try a fresh plug and make sure the battery is showing at least 12.5v which is essential if using electronic ignition.