Starting issues 17 exc 250

Hi chaps, I have got a 2017 exc 250. It has now got 10 hours on it and I've been out on it 5 times. It's only the last two times I have found she is a right pain to start from cold, on electric or the kick start and with/without choke. Once warm she starts like a dream. Nothing has been tampered with on the bike since it left the factory - that's a lie, I made sure the power valve spring square nut was fully wound out.

All that stands out in my mind is on the 3rd time out I was a litre or so short of a full tank so used a mates mix for his cr250 which is 40:1 to top it up. And after this ride I relocated the top two pipes off the carb (assuming they are breathers) to inside the top of the air box. I also made sure there was little slack in the throttle cable by adjusting on the handlebars.
It's only after this I have noticed starting issues when cold.

Has anyone any suggestions as where to possibly look, I considered the plug may have got oiled up by using a slightly richer mix. Only plug I have spare is a BR8ES (from my 16 model) and noticed the 17 model is a br7es.

Any suggestions are welcomed. Thanks

Buy a Honda 'Simples'

OWEN450X wrote:Buy a Honda 'Simples'

Says the husky owner

Have you rejetted it yet? Mines run like a dream since I sorted it out

mizzed wrote:Have you rejetted it yet? Mines run like a dream since I sorted it out

No havent rejected. I've had it around a month and they said the earlier ones had issues with jetting but that's all sorted now.

What sort of issues was you having to warrant rejetting a new bike??

Using lots of fuel and didn't like starting that much.

Any idea what jetting you have in there?

Whatever standard is, assuming easiest way to check is to read the numbers on the jets. How did you know what size to change them to? Frustrating you have to do this to a new bike! But funnily enough it is noticeably thirstier than my 16. I usually had around 70-80 miles on a tank. Ran out at 50 miles last week.

If it's drinking fuel it will need jetting, they all come really rich in stock form. I left mine as factory to break in then changed it and it's been great since.

Jets are easy can tilt the carb and drop them out of the train plug. The needle will need to come out with the slide.