Hwan's BSA 250 Scrambler

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Re: BSA 250 Scrambler

Postby hwan » Sun Mar 06, 2016 11:41 am

Bit of a disaster yesterday - friday night i realized that i could not seal the 75m bore barrel to the head - because of the std position oil drains.

Obvious really - and i had my doubts at the time and alarm bells were ringing when the engineer made the liner (but after waiting +9 months chose to ignore!) ..... anyway, seems i have three options;

1/ seal barrel spigot to the head, via machining and/or a 'ring' gasket - this then leave some tricky machining to get enough 'nip' on a modified std gasket to seal the oil drain and p/rod tunnel.

2/ the above + somehow machine around p/rod tunnel to fit 'O' ring (could use a modified std h/gasket to contain the 'o' ring and stop it squashing out) - but still leave problem of head oil-drains.

3/ make a head gasket to fit as std - but blank off the oil drains in the head and barrel. And then fit external/non-standard head oil drains ....

As they say - "if you've never made a mistake, you've never made anything !".

Bollox! :oops:

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Re: BSA 250 Scrambler

Postby hwan » Thu Mar 10, 2016 7:11 pm

Original R&R rod fitted to machined crank (for clearance) gave a balance factor of 31% - oops, didn't vibrate that badly honest!
Much drilling later, now nearer 54% for the 75mm XT piston and nearer 59% for the standard 250 piston - so vibration should be better ?

Spent lots of time polishing crank to a sliding fit in the main-bearings - better than the original hydraulic fit!
Now easier to re-assemble and there's somewhere for the crank to expand when hot.

MX cam fitted and .................... the followers hit the c/case - didn't realize there were two thickness's of follower foot - all my good ones are the thicker variety - light grinding to give 1mm clearance has sorted that!

Realized what everyone saying about oil pressure blow off valve - not located in the outer casings, but the t/side 'main' crankcase - so am stuck with a ball type valve - i think i'll fit a pressure gauge for initial runs to see whats happening.

Crankcase mouth already opened out by 0.5mm to allow 75mm cylinder to fit - so now have the option of 250 or 320.
Have worked out a method of draining the 75mm bore head - practiced on an old head - just need to buy some long drills, have a stiff drink and go for it!

The rebuild is on. :grin:

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Re: BSA 250 Scrambler

Postby hwan » Sun Mar 13, 2016 8:39 pm

After driving self mad setting up cam timing, with an engine now so free that the piston wont stop on TDC with the new balance factor - proceeded to move on.

See other thread about cylinder/capacity problems.

So decided to fit post 71 cam-drive cover - mainly cos it allowed fitment of an oil pressure switch and gauge.
As you all know the later covers have a larger oil-feed 'o' ring - so, new 'o' ring and +1hour at Cooky's (hell i wish someone would answer that phone) - back to the job in hand.

Looked at new 'o' ring and cover, then looked at 1968/9 crankcase ........... there's not much metal around the oil-feed hole ??!!
Some measurements later and i realize the 'o' ring will only just sit on the crankcase machining with the cover groove JUST holding it in place - all a bit marginal.

I did notice in HP's photo book, that he seems to take his pressure switch and gauge (interesting ....) from the crankcase pressure relief valve....?
Will have a look and see if its an easy mod - in which case, the old cover goes back on and the Post71 cover goes back on the post71 crankcases .....

I really, really, cannot say a good thing about bloody B25/44/50's at the moment ........

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Re: BSA 250 Scrambler

Postby beat » Sun Mar 13, 2016 8:52 pm

hwan wrote:I really, really, cannot say a good thing about bloody B25/44/50's at the moment ........


Hmmmmmm, strange..... <201

arn't this the best bikes ever :?: :?: &lt;069 B50icon b44icon <12fs

there must be wrong something else ..... <214

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Re: BSA 250 Scrambler

Postby HPbyStan » Mon Mar 14, 2016 2:48 am

What I tried to do with taking the oil pressure reading from the by pass valve was a bad idea. Please don't copy that one. Stan M

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Re: BSA 250 Scrambler

Postby hwan » Mon Mar 14, 2016 11:32 am

Beat - i'm probably looking looking to closely at thing ....?

Stan - thanks for the 'heads up'.

Have another VERY good look today.

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Re: BSA 250 Scrambler

Postby hwan » Sat Mar 26, 2016 10:24 am

Well, its running .....
In a massive cloud of smoke ..... from the cylinder.
A big DOH! moment when i thought i had broken through the casting when re-routing the oil drain - but no, just AFT all over things after measuring CC volumes.
Eventually burned off.

A quick blast up the A19 (including when battery fell off) shows it goes ..............
About the same as the old 250 !!!!!!!

It could be the newly installed high(MX) 1st gear disguising any improvements, but not what was expected.
My concern about the MX cam being 'too much' - completely unfounded - cannot even feel if/when it comes on the cam, it seems a bit more 'free revving' but that don't mean much as the 250 engine was tired - or to use an engineering term - bollox'd!

CARBS - Started on 28mm MK2 Amal - then 30mm OKO/KEIHEN - will try the 30mm AMAL MK2 (or a Mikuni30) for the dyno runs as i have so, much jetting for them.

IGNITION - Currently constant loss WASSELL on one plug, todays task to time up the Elextrex and find a twin output coil for the Wassell.

Only thing of interest is the difference between center and side plug - according to my kicking foot - Side-plug ignition is definitely more retarded than center plug - which figures. <12fs

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Re: BSA 250 Scrambler

Postby Mark Cook » Sat Mar 26, 2016 12:43 pm

You know better than to make more than one change at a time Nigel. I hope your notes are in good order?

BTW, for MX you want a flat response. Coming on Cam just wears you out and is for thrill seekers.
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Re: BSA 250 Scrambler

Postby hwan » Sat Mar 26, 2016 1:21 pm

One thing at a time ..... assumes you have the time and patience -
Times running out for me and patience was never my virtue.

Must have got too used to 2strokes - even the PE can get up and go when you are fresh and untired.
The entire rational behind tweeking the B25, which lets be honest is pretty limp thing, was to make it a bit more interesting.

Logically it would have been cheaper in money and time building a B44/50 - but as you know, logic has nothing to do with motorcycles.

As ever, i'm running late - this should all have been done before Xmas, but at the time the 3HW took priority.
Its early days, she is running a lot of cam (?) and not much compression + there's ignition and carb to sort out + suspension (again).

Being positive, it runs and those springs you sold me and Andy seem a lot better bouncing round a field, than they do in the shed - so some progress.

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Re: BSA 250 Scrambler

Postby Andy Chaos » Sat Mar 26, 2016 1:40 pm

So apart from the cam, the carb, the ignition, the compression ratio, and the suspension, every thing else is OK :thumb
Ariel back on the road if you need recovering :ban
Last edited by Andy Chaos on Sat Mar 26, 2016 5:58 pm, edited 1 time in total.

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Re: BSA 250 Scrambler

Postby hwan » Sat Mar 26, 2016 4:17 pm

You missed out the bent exhaust that I've done ..............!

As for Ariel being rebuilt (again) to recover me ...............?
Maybe the B25 but not the Norton (i bet i regret saying that ..)

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Re: BSA 250 Scrambler

Postby hwan » Sun Mar 27, 2016 11:35 am

Should have done the plastecene trick - to check piston valve clearance, tried blutak but not the same.

One BIG advantage of the non B25 engines is the screw type valve clearance adjustment - i usually take up all the clearance, then wind it in another full 1 turn for R/racing or for MX, 2 - and than CAREFULLY turn the motor over to see if anything catches/hits, etc.

Simple an quick as they are usually 1/4" BSC and one full rotation gives about 1mm.

Now re-assessing situation .....

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Re: BSA 250 Scrambler

Postby hwan » Wed Mar 30, 2016 10:07 am

Two exhaust valves later - have found the problem ..............
Completely underestimated how offset the XT250 piston exhaust valve cutaway is from the centerline of the engine - the very edge of even attempt #2 modified valve cutaway - was catching the valve @4000rpm .........

One new G&S valve later (the only good thing about BSA's is spares availability from PES !!!!), considerable measuring and assembling engine without head gasket with a 1.6mm piece of ali lifting the valve higher than normal (mod of the screw the adjuster in trick).

WP_20160329_16_56_49_Pro.jpg


And she is running again - this time actually restarting as it still has compression !

While she was apart - got out the plate glass and flattened the head gasket surface - there were worrying signs of blowby under the exhaust port - and flattened the rocker-box to try and reduce oil leaks from this area.

And while i was at it, Lambda sensor, oil-pressure gauge, cylinder temp gauge and Scitsu where fitted - if no Dyno runs, i can blast it up the road and see what i get!

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Re: BSA 250 Scrambler

Postby Mark Cook » Wed Mar 30, 2016 10:18 am

The lengths some people go too, to provide us with entertainment ;-)

Thank you for the plug and well done Nigel.
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Re: BSA 250 Scrambler

Postby HPbyStan » Wed Mar 30, 2016 2:50 pm

Blasting up the road against a known commodity is better than a dyno in some ways anyway as one gets a real world comparison. I would run the B50 against the best 500cc Rotax I knew of and they ended up pretty even. Whichever bike I rode was slightly quicker as I was lighter weight than the other dude. On the race track my chassis and the 2 valves smoother power delivery than a 4 valver plus good riders made the B50 very hard to beat. Jimmy Sumner was really bad at getting off the line so once in awhile they would throw the checked flag before he got all the way to the front but he was almost never passed. In his Junior class year he won every heat race all year and finished worse than 3ed only once in a feature when he, for some reason, rode most of the race in3ed gear at a race meet where he was the fastest in timed practice of any classes including the the experts on 750s. I'm still kinda mad that after all the over achieving we did that the B50 was only protested and measured twice. Both times we were legal, any damn fool can cheat and most of them are imo.

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Re: BSA 250 Scrambler

Postby hwan » Thu Mar 31, 2016 12:09 pm

Not a good start to the day -

First the BMW F650 w/pump seal went ......

Then fitted another pressure gauge on B25 and the oil pressure ACTUALLY reads 35-45psi .... when coldish :(

Then while checking ignition timing as i revved it to 8000rpm its bent another valve !

Not a happy bunny.
Now in fetal position, sucking thumb <218

As Andy has already burned my Engineering degree, i'd better give him my HNC & HND certificates as well ...... <218

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Re: BSA 250 Scrambler

Postby baz » Thu Mar 31, 2016 4:56 pm

hwan wrote:Not a good start to the day -

First the BMW F650 w/pump seal went ......

Then fitted another pressure gauge on B25 and the oil pressure ACTUALLY reads 35-45psi .... when coldish :(

Then while checking ignition timing as i revved it to 8000rpm its bent another valve !

Not a happy bunny.
Now in fetal position, sucking thumb <218

As Andy has already burned my Engineering degree, i'd better give him my HNC & HND certificates as well ...... <218

just incase you dont already know have you ground off the valve lifter casting on the exhaust rocker ? although 8000rpm isnt that high for a b25 best of luck with it these motors are great fun to work on cheers baz

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Re: BSA 250 Scrambler

Postby hwan » Thu Mar 31, 2016 7:57 pm

Well, its in bits again.

Checked timing, checked damn near everything else and cannot find whats happening.
When i consider that it felt rough from get go this morning, i suspect things had already collided before i wound it up to 8K.

There is evident of valve piston contact - so, as i cannot afford to bend any more valves (i have tried straightening them but...) - i will have head-seats cut deeper + deepen valve cutaways in piston. As its easier to do this than retarding cam timing (or is it advancing ?) or doing anything with cams.
so question -

HOW LITTLE CROWN THICKNESS can i get away with ON A CAST JAPANESE PISTON ?

I've drilled a hole through an old piston (hope Stuart don't want his piston back?) and there is only 6mm to start with - i wanted to machine 1-2mm deeper - is there enough metal, you experts out there .......

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Re: BSA 250 Scrambler

Postby HPbyStan » Thu Mar 31, 2016 8:40 pm

Dunno BUT advancing the cam puts the inlet valve in pearl and retarding the cam does the same for the exhaust valve. I wish BSA had those eccentric rocker arm shafts stuck in their corporate rear ends. With rocker arms that short, any advantage is totally on paper and not real world. I never tried C15 rockers on a B25 but I wonder if they would fit and then one could use the eccentric shafts to just locate the adjuster correctly over the valve stem.

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Re: BSA 250 Scrambler

Postby hwan » Thu Mar 31, 2016 8:53 pm

Stan - is that peril ....?

She's timed 100deg atdc max Inlet lift, as per PES info - but this is of course for a B44/50.
Where it wants to be for a 320cc big inlet valve B25 on a straight 13/8" diameter pipe - i guess is another story.

One thing the short runs have indicated is a very sharp crack from the exhaust - i know from experience with a 2stroke, either exhaust is wrong, or there's excess Exhaust timing (or more usually both).
Wonder if exhaust is opening too early (or the pipe too short?) - in which case does it want cam retard - back to 103 or something?

As i say, its a real bind changing cam timings - one day when i get the Dyno working i'll modify a set of cases so i can to the cam more easily.

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Re: BSA 250 Scrambler

Postby HPbyStan » Thu Mar 31, 2016 8:55 pm

HaHa, peril does look better. My spell checker wouldn't get me out of that one. A sliding extension over a straight pipe might get that exhaust tuned in for you. If the valve timing is bouncing the exhaust valve off the piston, retarding the timing will MAKE IT WORSE. You might try shining a flash light into the spark plug hole and you will be able to see how much / if you have valve clearance. On this side of the puddle we don't stick a lit torch into the combustion chamber with the inlet valve open, just too much excitement.
Last edited by HPbyStan on Thu Mar 31, 2016 11:27 pm, edited 4 times in total.

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Re: BSA 250 Scrambler

Postby beat » Thu Mar 31, 2016 8:58 pm

hwan wrote:its bent another valve !

hwan wrote:i have tried straightening them


Hmmmmm <201

if this not works, -- what about - bending the Valve Guide two to have it equal ??

( just as a logical Idea.....)

:oops:

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Re: BSA 250 Scrambler

Postby minetymenace » Thu Mar 31, 2016 9:42 pm

:laugh
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Re: BSA 250 Scrambler

Postby Chris Pellett » Fri Apr 01, 2016 7:46 pm

Years ago when fitting an Omega piston into a B25 I was told to machine the cutaway parallel to the valve so that when it hit the valve the valve would not bend.

I did not bother and the valve bent!

Cheers
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Re: BSA 250 Scrambler

Postby hwan » Sat Apr 02, 2016 3:02 pm

Well, it seems i was mis-reading what i was seeing - it seems i now have a running engine + severely dented ego.

Re-cut piston cut-out as deep as i dare ~1-1.5mm - to match different position of valves (between XT and B25) + talked Mr Cook into cutting exhaust valve seat 1-1.5mm deeper - despite agreeing with him about whether it was the 'correct' way of going about the problem.

A really big THANK YOU PES - its the only good part of B25 ownership, being able to get quality spares as readily as i can with u guys.
But PLEASE get Anita (i can see her rolling her eyes even now) back on the phones so two cantankerous old farts don't spend hours at each visit talking about stuff ........... :laugh

It is a sort of engineering BODGE but is seems to have done the trick.
Deepening the exhaust seat is on old trick - I've usually had to do on triumphs, to stop valves hitting each other during overlap. Well documented to have no detrimental effect on flow, just lowers the CR a little.

So, engine now running - 30mm Mikuni now fitted (already jetted for the B25) as the OKO/Keihen was hanging open a bit when revved - not a happy thought.

Oil pressure gauge not a good idea .............. only 25-35 psi when warm, though there is a good flow.
The original engine ran like this for +1 year so will ignore/remove and fit a pressure switch ............ which brings us to pressure switches!

The original switch (also shared with triumph twins) has an operating pressure of ~5-10psi - which i thought was too low, so i sourced an automotive 18-20psi switch. The correct/original switch is getting fitted, as i can see the automotive one, flashing at me all the time !

Will also change to a thicker oil than the thin (free) synthetic stuff i use - would like to change to 'R' but cannot be arsed flushing stripping etc.

So - next thing is ignitions .... standby for the next thrilling installment ........... <216

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Re: BSA 250 Scrambler

Postby beat » Sat Apr 02, 2016 8:06 pm

hwan wrote:Will also change to a thicker oil than the thin (free) synthetic stuff i use


take care hwan, - this change was costing me once a new piston and a rebore.....

beat <218

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Re: BSA 250 Scrambler

Postby HPbyStan » Sat Apr 02, 2016 9:12 pm

Somebody mentioned Ams/Oil 20W/50 as a good choice. I heard he has had some success with it. <1011
One doesn't have to change it after every heat cycle, one can run it a whole season so the cost on a season basis is still low.

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Re: BSA 250 Scrambler

Postby hwan » Sun Apr 03, 2016 10:30 am

Yes I've been told about the Amsoil's - i understand they still contain the zinc/lead/whatever additives originally used to combat cam wear (in VW's etc.) - not used now in common oils cos they bugger up cat's.
Not commonly available in the UK it seems.

I do like 'R' - not to wind you up and certainly not getting involved in any oil debates - i did wonder how synthetics mix/react with 'R'
i.e. is a full strip clean needed when swapping , or running through 7 dumping, a couple of litres of 'R' with minimal load - would be enough ...
Anyway - got enough problems for now, but did wonder.

Anyway - currently fascinated by the way this engine responds to being ignited from the two different plug positions ....

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Re: BSA 250 Scrambler

Postby HPbyStan » Sun Apr 03, 2016 2:08 pm

Castrol used to sell a "flushing oil for getting rid of "R". Don't know if they still do.

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Re: BSA 250 Scrambler

Postby hwan » Mon Apr 04, 2016 10:53 am

Guess i'll stick with a thicker grade of mineral oil - at least my chain-case doesn't share oil with engine so i can use the wider range of car oils.

The oil pressure gauge is a bit of a 'red-herring' as it ran ok through last year, it was really in response to an inquiry on here about oil pressures. #

You don't get worried about something you don't know ...... pity i now know!

Ignorance WAS bliss !

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Re:Hwan's BSA 250 Scrambler

Postby hwan » Wed Apr 06, 2016 7:59 pm

M.M - can you please transfer this to 'project bikes' as that's what it is really - please :thumb
(Edit by MM, your wish is my command!)

Update - was going to show pix of a set of crankcases stripped down to nothing in a frame - as that's what happened.

Realized i couldn't sell a bunch of bits or a bike that don't work - so decided to strip and rebuilt it back to 2015 condition ...........................
So that's what i have done all today (isn't retirement lovely)

Except that the old 250 head has been robbed of its exhaust valve (same as all others in the shed) and anyway the guide had been moving up/down with the valve and the head was comprehensively shagged !

I had meticulously timed up the MX cam so that inlet max lift was 100deg ATDC - so never bothered to actually check Inlet/Exhaust open/close points .... the way i would have done it on a Triumph twin. A quick check of the timings made no sense whatsoever - so its been removed pending further investigation later.

Std. B25 cam + wheel, refitted and timed on the V mark - which may have been a mistake as it appears (according to BSA w/shop sheet) one tooth advance ... F###-#t - it ran ok before - so it got left.

Checked valve in 320 head and they are still straight (?) - took out compression plate and rebuild.
MISTAKE - cannot kick the bloody thing over (duff knee) - not what was planned, and the reason why i avoid the 450/500's

So after spending one hour f*****g about with push-rods to fit different cam and no compression plate - then spent another 1/2 hour re-adjusting when i refitted the CR plate .................. <218

Wouldn't start ..........
Elextrex - playing up - sorted when i discovered the crank retaining nut wasn't actually tightening rotor onto the taper - so yet more machining, to make it all work (was no problem least year ?) - only snag no is that it is way retarded and VERY firmly locked onto the taper - so an extractor needs making - tomorrow i think!

Wassell comes to the rescue - despite a dodgy plug (?) which stopped it sparking - it now works and has got the piece of s**t running ...
If the Elextrex don't go back to its 2015 total reliability and easy starting - i'll go wassel as i have a small battery on order the regulator and a Lucas genny.

Actually sounds better - has considerably more compression than before (the B25 primary gearing ??) - only snag now is that the oil pressure has sagged off to 25 psi.

I wonder if the guy i sold the PE to would loan it me back ?

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Re: Hwan's BSA 250 Scrambler

Postby hwan » Fri Apr 08, 2016 7:03 pm

Finally some light at the end of the tunnel (just hope its not a train!).

Trying to revert engine back to 2015 spec - just could not get the 'self-generating' and totally reliable Elextrex ignition to run the bike ?

Had the wassel working fine, even got a regulator/rectifier + Battery + Lucas alternator sat on the bench - but just couldn't get the Elex working?

After fixing strobe, had engine running on Wassel with Elex also fitted and checked both on the strobe - both timed up where they should be, yet when i disconnected the Wassel battery - it stopped with a loud BANG ?

Checked and re-checked & kicked until my back went again ................ no run, much cry! <218

Removed Elextrex and gave it a good examination (again) - all looked good - BUT rotor has one blackened timing mark and an unpainted one - the instructions say there should be a red timing mark .
For some reason i've been using the black mark - assuming they simply changed the color - after all it was strobeing up as expected ?

Retried it all again but using the unpainted mark (180 deg opposite) - and BINGO - she runs well :ban

So i'm back to 2015 spec but 320cc instead of 250 - but why was it strobeing up exactly as if it was on the 'firing marks ?

Only got to change the tires tomorrow (with a bad back ....), remove the wassel (sorry Keith but it have to wait till later) - and generally bolt foot-rest and things back on, as if i'm ready to race ?

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Re: Hwan's BSA 250 Scrambler

Postby beat » Sat Apr 09, 2016 7:35 pm

hwan wrote:the unpainted mark

put a Flag on it ! <053

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Re: Hwan's BSA 250 Scrambler

Postby hwan » Sun Apr 10, 2016 5:45 pm

:grin:

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Re: Hwan's BSA 250 Scrambler

Postby hwan » Mon Apr 11, 2016 7:02 pm

So, off to Elvington sprint practice tomorrow - with luck it will rain - so my S12's don't get chewed up on the tarmac and that i can get a few blasts around the apron roads, before someone stops me.

Anyway that's tomorrow, tonight went through my repertoire of carbs and it seems I've achieved something as my flat-spot has gone away and they all carburate, something like?
Question - is it more compression, more capacity or the center plug ?

If i still have some oil pressure, looks like I've got something to race on Sunday :cry:

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Re: Hwan's BSA 250 Scrambler

Postby hwan » Mon May 16, 2016 7:42 pm

Star date 14.5.2016 - BOOTH FARM ENDURO - BUXTON (UK)
Its first outing this year wasn’t a total disaster, the bike, rather than the rider managed to finish a 2 hour enduro ……………….

Didn't start well as I a fried the clutch trying to get up to the start of the ‘viewing lap’ – it just wouldn’t pull, despite trying a variety of gears – 1st, 2nd even third …?

On the way back to the pit area – down hill luckily as the clutch had given up, I realised the problem ….. I’d fitted the gearbox cam upside down – no surprise it wouldn’t pull up the steep hill in 3rd or 4th !!!!!!
Or should I say that I should have been surprised that it even tried to ?

A stupid mistake - yes, but I was surprised how difficult it was for me to adjust to the upside down gearbox – once I’d bodged the clutch back into some form of action (couldn’t kick start it).
Even after 2 hours, I was prodding for the wrong gear, at the wrong time, in the wrong place (side of a steep hill).

Away – finish we did, the plug mounted temp gauge was off the clock @ 220-240 degC, she felt as hot as I did, with a lot of cooking oil smells (mineral not veg).
There was a miss-fire which came and went (water and bits in carb?) + the carb started to hang open, right when I didn’t want (the throttle is way too light for off-road use, a bump giving power when I don’t want).
And there was absolutely NO OIL LEAKS ??

In fact then engine is so squeaky clean around the rocker-box/head area, I thought I’d lost rocker oil supply (I haven’t) ……..
I’m a bit heavy with grease when fitting head-gaskets (and measuring compression ratios) and I wonder if I’d blocked the oil drains with the stuff – the extreme engine temps, melted it away and allowing the oil to flow freely ….. only thing I can think of ?

So do it go any better?
Well, yes – it now even feels under geared, despite having the much higher MX first gear.

So what next;

1/ obviously sort the clutch out….

2/ Ignition – I strongly suspect the timing was retarded – but as the Elextrex is such a bitch to adjust in the field – I will be fitted the Wassel + twin plug ignition, as I know it seems to give a much better ignition curve (more advanced at low speed) – allowing the use of a different carb.

3/ Remove the OKO/KEIHEN carb – its only fitted because this is the only carb that will live with the Elextrex. I will be sticking with 30mm but is could be Mikuni or M2 Amal – depends which I can get carb’ing better.

4/ Fit a charging system for the Wassel.

5/ do something about suspension – as it now seems to be going better, all its done is highlight suspension failings ……. <12fs

6/ learn to live with the upside down gearbox – it’s the same as my 1932 Norton – so I should be able to live with it – but seems so natural simply being able to stomp on the lever to select a lower crawl gear, as I slump over the h/bars with exhaustion.

Image

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Re: Hwan's BSA 250 Scrambler

Postby minetymenace » Mon May 16, 2016 7:57 pm

:thumb...thanks for the report....It says Trumpet on it!!
Abyssinian Wire-Haired Tripehounds Gnash.

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Re: Hwan's BSA 250 Scrambler

Postby HPbyStan » Mon May 16, 2016 8:32 pm

Real BSAs shift up for 1st.

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Re: Hwan's BSA 250 Scrambler

Postby AJ CCM » Mon May 16, 2016 8:40 pm

HPbyStan wrote:Real BSAs shift up for 1st.

:thumb <1011
Regards AJ CCM

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Re: Hwan's BSA 250 Scrambler

Postby Andy Chaos » Mon May 16, 2016 8:48 pm

Here you go Whan my first attempt with the gopro, you can see your triumph at the beginning then 3 B50s and my CCM
I know its only short but I didn't fancy attaching it to my helmet for the first time.
You wouldn't believe that the same track was 2" deep in snow the weekend before.
https://youtu.be/-HAh2rZIpwE


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