Author Topic: Surging, dying motor after 4K revs :(  (Read 1140 times)

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Birdy78

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on: July 20, 2020, 09:41:59 pm
Hi everyone, I’m new here to the board, but have been reading the forum for months. I have just joined the ranks of Enfield owners, bought a lovely CGT back in may after selling my Yamaha SR500 café racers - I figured I could do with a challenge ;) So far I haven’t been disappointed, there are more bugs with this bike than on my helmet!

I wanted to write a post to see if anyone has some wisdom with the only problem I haven’t been able to fix yet :( I’m riding a CGT 2015 EFI with a stock engine and exhaust, most of the changes on the book so far have been cosmetic. It rides beautifully around the twistys, and the engine loves being between 2K - 4K, but as soon as I take it sustained over 4K, then the engine surges like someone is pinching the fuel line. One time this happened was on a quick trip on a highway (15km), and the engine then died after I had slowed down when I had reached the town where I was heading. After letting it stand idle for half a day, the motor then started up fine again. It seems to be a problem that develops the longer and more intense the trip is. If I take it up to 4K and then fully open (Blip) the throttle, then I can hit the rev limiter at 6K while accelerating, but as soon as I try to keep it at a sustained 45K then it surges and splutters again.

So far, I have:
- Checked all wiring (seems ok)
- Checked the battery and connections (fine)
- Checked the ignition wiring (ok)
- Checked the fuel line (not kinked)
- Looked in the tank (dirty but not rusty, I think)
- Have removed the side stand switch
- Mechanic thought it was the rev limiter

I will get the tank off soon and have a closer look at the pump, and will probably get a new exhaust, filter and power commander at the end of summer, but apart from that I’m stumped...

Any ideas?


gizzo

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Reply #1 on: July 20, 2020, 11:04:40 pm
I probably sound like a broken record by now but I'd be changing that fuel line. The stock one is poor quality.  Maybe it's collapsed inside and restricting fuel flow. I swapped mine for automotive fuel hose. A long enough piece that it loops back over the battery to eliminate any kink.

Hope your fix is an easy one.
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ace.cafe

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Reply #2 on: July 20, 2020, 11:36:36 pm
As Gizzo says, that fuel line is a known trouble spot. Sometimes it is visibly kinked or pinched.
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Arschloch

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Reply #3 on: July 21, 2020, 07:44:56 am
I can recommend a fuel line braided in stainless steel on the outside that keeps the hose bit form stable. After trying a couple of hoses with reoccuring issues, this sort of fule line finally solved it for good.


Birdy78

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Reply #4 on: July 21, 2020, 09:48:41 am
wow - thanks for the quick replies! I didn't know the inside of the hose could also be a problem - I'll whip that off and get a new one on pronto!