Bantam D10 - Engine problem

[Little Bantam D10]

Hello everyone, I am chirot. I just bought Bantam D10 a week ago. Always first kick start. However I have a problem with the engine. It always stop in middle of the road when I ride at speed of around 30 mph for around 5-10 mins. And then I have to wait for 5-7 mins before I can start it again. The piston still moves freely when It stops. Thought the fuel tap was too tight, so the inside tank under vacuum condition. I tried by riding it with the fuel tap open. The problem still occurs. I could be killed!!! Does anyone know what the problem and how to fix it? Pleas give me some advice.

[Goldie]

I would start with the simplest jobs first.

Take carb off and clean out.
There could be a bit of dirt around the main jet or somewhere else that is moving around. Check that the float is not sticking, and cutting off the fuel supply.
Have you taken the fuel taps out of the tank and cleaned out the filters. They could be bunged up and not letting the fuel through fast enough.
I would also change the plug.

It could be a process of elimination.

[Searchguru]

Chirot,
I think you are saying the fuel cap is causing a vacuum in the tank. If that was the case then riding the bike without it attached should have shown that the bike worked. As it still died on you then it is not the problem you thought it was. I agree with everything Goldie says and carry a spare spark plug with you. If the bike stops take the spark plug cap off the plug in the bike and fit it to the new plug. Rest the new plug on the cylinder head and kick the bike over. If you can see the spark plug sparking as you kick the bike over then it is clearly not an ignition fault and is fuel related. Wait for your 5-7 minutes and do the same again. If it was not sparking before and now is that would show that the problem is electrical. Let us know the outcome and it will be easier to diagnose, with a bit of luck.

[Little Bantam D10]

I have already clean the carb, the bike never stop again. When I took it out for runs, it couldn't make satisfactory speed (38-40 mph). Therefore I changed the carb to a little bit bigger size, the speed increases to 40-43 mph.
Also there is an oil leaking under the engine, I wonder whether it is normal for BSA Batam (Someone told me oil leakage is normal for BSA motorbike).

This is my first time with english bike, need a lot of advices. Please please dont get annoying yet.

I want to set the timing, but I have no idea how to do it.

[geoffus]

 :)hi you could try taking the plug out next  time
this happens and see what colour it is white weak mixture black to rich  brown good you say you have oil coming from underneath the motor if this is coming from the crankcase you may have a problem of no crankcase compression when hot however is most likely coming from the gearbox probably the kick start as you have cleaned most of the parts I think it comes back to crankcase compression when hot then have a look at the Plug as this will give you some indication of what was happening when you stop    geoff

[Little Bantam D10]

There are oil leaks at 2 places; kick starter and between joints beneath crankcase. The one from kick starter has clear colour, whereas another one is black.... Also there are some weird noise in the crankcase on the gear side.  Is this normal?

Also the engine lose power.... Umm I feel like the ignition doesn't continuous consistently while I am accelerating.

Do you guys experience this???

[Goldie]

Sounds like you have a few problems.                                       Take the engine out of the frame, and fully dismantle.
Its the only way you are going to find out whats going on.

Don't be afraid. They are very simple engines to work on providing you have a workshop manual.

[geoffus]

 :)I think your best bet is to take goldies advice and do a complete rebuild  black oil is an indication that you are losing crankcase compression and as mentioned Bantam motors are fairly simple and you should be able to pick up spares fairly easily   geoff

[Little Bantam D10]

There are a lot of compression when I kick start which almost breaks my foot for several time. However I have already thought of rebuild the engine to get fresh start with English bike experience... I am still afraid that I couldn't get spare parts and it will take too long. Really enjoy on bantam!!! Also I have only had Bantam D14 work manual and D10 intruction manual. I need to thank Goldie for website recommendation. Oh I am in Melbourne, Australia by the way, not in UK. Maybe you guys can suggest somewhere I could get good price for parts!!!

Many many thanks to all

[Little Bantam D10]

Sorry, mistake. hehehe I need to thank for encouraging me!!!

[Goldie]

When i restored my 1958 Bantam D1 125, i used T&G Motors for all my spares.

http://www.mistgreen.com/spares.htm

Good Luck