Grandsons beta 80 big wheel, not running like it should Cutting out and balking ,seems like a fuel/carb problem. Cleaned out the carb changed the plug but still no joy wondering if anybody has had similar problems or could offer any tips on getting it running right.Thanks in advance.

What I have found with little bikes is that the slow running jets and galley ways are so small that they easily get blocked and are very difficult to clear out.

Does the bike tick over okay? I have found if the bike will not tick over as normal then the carb needs cleaning and this can be after a fall with the bike etc. Once all cleaned the bikes run well again and only takes a few minutes to clean so just practice. Apart from that they are pretty much bomb proof and just techniques for starting if cold, if crashed or warm so I would start with the crab and ensure you clean all the jets out

Does not tickover as it should very lumpy the grandson says.Seems as though it is being starved runs very uneven.

 

On our bike I would say 100% the carb but just need to check air filter is clean, pipe work from air filter to to carb has no moisture and then fuel supply is clean. Jets are very small so ensure you can see through each one before putting carb back together. if you are a member of a club I am sure there will be somebody there who has experienced the joys of these bikes. They do work very well but need a little TLC

Was it running ok previously or has this just started. These bikes have a poor petrol tap. They can become very stiff to fully open, always a possibility that the tap isn’t functioning. Had to replace one on my sons for exactly this reason

56 minutes ago, timdog said:

Was it running ok previously or has this just started. These bikes have a poor petrol tap. They can become very stiff to fully open, always a possibility that the tap isn’t functioning. Had to replace one on my sons for exactly this reason

You can get a lever style fuel tap from these guys : https://www.trialsuk.co.uk/Beta-Fuel-Tap---EVO80REV80REV50---Lever-Style?search=fuel tap

More efficient & easier to use.

2 hours ago, anachronism said:

You can get a lever style fuel tap from these guys : https://www.trialsuk.co.uk/Beta-Fuel-Tap---EVO80REV80REV50---Lever-Style?search=fuel tap

More efficient & easier to use.

 

2 hours ago, anachronism said:

You can get a lever style fuel tap from these guys : https://www.trialsuk.co.uk/Beta-Fuel-Tap---EVO80REV80REV50---Lever-Style?search=fuel tap

More efficient & easier to use.

Thanks for the info,got it in the shop now hope they can sort the problem.Gutted for the grandson should be out in this fine weather.

Hi all Beta Evo 80 owners with a fuel problem.  I have had my grandsons bike from new in 2021, it ran great for the firs 6 months and over time has developed a fuel starvation problem

Have spent the last 2 days stripping every thing down to eliminate the obvious.

Then I had a brilliant idea , my Beta 200 was standing next the 80, I took fuel cap off and sucked the cap , great air flow, I took the 80's cap off and sucked and sucked , now air floe, I put the air compressor on to the inlet side after I took the non return valve off , absolutely no air,\ flow 

The cap has a plestic disc up inside the extended skirt, this has 6 small holes less then half a mm on diam

Some plastic absorb liquid and swell hence the holes closed over

Use a small pin punch inserted in the out side top of the cap and knock the disc out, drill the holes to 2mm and clean all swarf , reinsert disc, Bingo air flow , no more vacuum formed in the tank causing fuel starvation,  

 

I agree with timdog, for I had the same issue on my 2022 EVO 80, and it was lack of fuel flow related.  I fully opened the OEM fuel tap, checked for adequate fuel flow and installed an inline shut off valve.  No more issues.