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BETA ALP 4.0 - a trailbike
https://www.trf.org.uk/forum/viewtopic.php?f=35&t=18191
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Author:  Hugh Cleary [ Thu Aug 06, 2015 2:33 pm ]
Post subject:  Re: BETA ALP 4.0 - a trailbike

Hello Thomas,

All things being equal, i.e. good compression; spark at spark plug; speedy engine cranking; petrol and air available in correct strength then the engine should start ;)

However, nothing is ever as it seems on paper :(

I have found by my own experiences that with a carburettor engine and modern petrol that it is always preferable to switch off the petrol supply and let the engine run until the carburettor is dry :idea: then switch off the ignition. Modern petrol is so much of a mixture of chemicals that the essential ones evaporate very quickly and the residue either corrodes the inner parts of the carburettor and/or fails to ignite during starting.

Might I suggest that you; switch off the petrol tap; drain the carburettor of any 'petrol' it has in 'store'; leave the drain screw loose and then switch on the petrol supply to flow some fresh petrol through; secure the drain screw; lock wire the drain screw so that it can not fall out on the lanes; allow the area to vent and then retry to start.

Normal starting requires the choke when cold and I do not operate the throttle until the engine has fired.

Try this and get back to me with any result.

TTFN

Hugh.

PS Mario - the file is too large as a PDF and I lost the original file trying to make it smaller, will try again later.

Author:  johnnyboxer [ Fri Aug 07, 2015 7:11 am ]
Post subject:  Re: BETA ALP 4.0 - a trailbike

Hugh Cleary wrote:

I have found by my own experiences that with a carburettor engine and modern petrol that it is always preferable to switch off the petrol supply and let the engine run until the carburettor is dry :idea: then switch off the ignition. Modern petrol is so much of a mixture of chemicals that the essential ones evaporate very quickly and the residue either corrodes the inner parts of the carburettor and/or fails to ignite during starting.

.


That's exactly what I do, every time without fail

Author:  Hugh Cleary [ Sun Aug 09, 2015 5:55 pm ]
Post subject:  Re: BETA ALP 4.0 - a trailbike

Folks,

Here is a link to the file which shows how I replaced the clutch thrust washers;

https://drive.google.com/file/d/0B1BIdt ... sp=sharing

TTFN

Hugh.

Author:  TGJR [ Thu Aug 13, 2015 8:15 am ]
Post subject:  Re: BETA ALP 4.0 - a trailbike

Problem found in fuel feed to the carb!

There was a bit of muck in the metal elbow where the fuel enters the carb and it was acting like a floating valve! It would appear that when the fuel tap was turned on the flow of petrol was flushing the bit of muck to the inlet jet and cutting the fuel supply.

Think we are there now and seems to be running well!

Thomas

Author:  Hugh Cleary [ Sun Nov 29, 2015 3:09 pm ]
Post subject:  Re: BETA ALP 4.0 - a trailbike

Update on Beta Alp 4.0.

Greetings folks,

Thought that I should give you a SAFETY update about running the Beta Alp, although not limited to just a Beta :roll:

During a run out last weekend a strange coincidence took place when John riding his Yamaha Tenere lost the friction material from its rear brake, not more than perhaps two miles later I lost the complete rear inner brake pad :o The first I knew was the total loss of rear braking :shock: :shock:

At the time I was convinced that both pads should have been retained by two pins through the upper ears but actually the inner pad simply sits inside of a cut out in the caliper support bracket, not untypical especially for KTM models as one of the other riders had experienced something similar before. Any way the moral of the story is that you must regularly inspect the inner pad and probably replace the pair if the inner is getting towards 2mm thick. New pads only have about 4mm of friction material :!: I was thinking of having a line of weld built up under the retaining ears in an effort to stop this happening again but upon further reflection perhaps I will simply replace the pads earlier than anticipated.

Here are some photos which might help clarify.

Attachment:
piston at full stroke.jpg
piston at full stroke.jpg [ 385.55 KiB | Viewed 8926 times ]


Attachment:
width 56mm.jpg
width 56mm.jpg [ 512.13 KiB | Viewed 8926 times ]


You might also like to know that a genuine replacement clutch lever costs over thirty pounds, an option is a copy KTM version which was only just over eight pounds.

Attachment:
clutch lever.jpg
clutch lever.jpg [ 324.68 KiB | Viewed 8926 times ]


Just need new pads now :oops:

TTFN

Hugh.

Attachments:
caliper in bracket.jpg
caliper in bracket.jpg [ 437.33 KiB | Viewed 8926 times ]

Author:  Joel [ Sun Nov 29, 2015 5:20 pm ]
Post subject:  Re: BETA ALP 4.0 - a trailbike

Mm mm Beta...testing...

Author:  Hugh Cleary [ Wed Dec 02, 2015 7:53 pm ]
Post subject:  Re: BETA ALP 4.0 - a trailbike

Greetings,

Update regarding the rear brake pad issue. I have just bought a new set of pads, not as straight forward as one might think as the callipers seem to change during production, anyway for my particular bike the wider 56mm inner pad is required.

I have tracked down that EBC product identification FA067R is the most suitable (well it fits the hole so I will have to wait and see how they perform 8-) ).

Attachment:
Alp inner rear pad.jpg


TTFN

Hugh.

Author:  Joel [ Wed Dec 02, 2015 8:17 pm ]
Post subject:  Re: BETA ALP 4.0 - a trailbike

Looks like bad design that Hugh....

Author:  RobPeel [ Thu Jan 21, 2016 1:20 pm ]
Post subject:  Re: BETA ALP 4.0 - a trailbike

Thanks for the tip on the rear brake Hugh. I've had a similar experience whilst on the trail.
Just about to replace front pads but caliper pins seized (ah! copper grease should have been applied). Anyway looks like I need to replace caliper. Apart from Beta (c.£150) any idea on pattern part replacement. Or anyone else?
Cheers
Rob

Author:  Hugh Cleary [ Thu Jan 21, 2016 10:07 pm ]
Post subject:  Re: BETA ALP 4.0 - a trailbike

Hello Rob,

Seized callipers on the pins is not uncommon to any marque. I have found in the past that you can sometimes get the little rascals to part by;

clamp the caliper support in a vice, gently and carefully heat the housing around the pins and then try levering them to separate
if that does not work try drilling a small hole in the end of the pin enclosures sufficient to pass a parallel pin, note not a centre punch
turn the caliper on to its side and squirt some WD40 type lube and leave to soak; clamp the support back into the vice and then try impact with the parallel pin, once apart clean the pins and holders; remember to use epoxy or similar to close up the holes
apply anti seize grease to the pins before reassembling
some folks have fitted a grease nipple and pumped the parts apart, but that has never worked for me

If you still have problems but can get the parts to me then I would be happy to try and sort it for you.

The same callipers were used on other bikes so you could check out with a breakers.

Hope these ideas might help

TTFN

Hugh.

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