Problem with a flat spot when accelerating
Discussion
Not sure but your carbs could be set up wrong, assuming you're on carbs. Might be a good idea (if you have the money) to go to a rolling road in your area and get it looked at by a specialist, or at least someone who knows what he's doing. It sounds like a fueling thing to me though, which might be accentuated by your stage one kit.
I had the same problem when i first fitted the stage 1 kit, it had a huge flat spot so i changed the needle and refilled the dashpot using 3 in 1 oil as advised by a expert. So i tried again and still had a flat spot, now the problem was the oil was to thin because when i put some thicker stuff in "hey presto" no flat spot.
Also like you say, you may be running to lean, if you,ve changed from a standard airfilter to a KnN style filter or any other performance filter then this will almost certainly be the case, i was running on petrol fumes at 2000rpms when i fitted my KnN cone but you will only find this out when you put her on the rollers. Im in birmingham near the city center, there is a guy close by who is known as mr mini. Hes a honest guy and knows his stuff he charges £45 per hr £55 for 2 hrs. He did about 7 or 8 runs in the 2 hrs untill he was happy, he took my carb apart and cleaned it, replaced the needle and dashpot piston and set the carb up and she ran like a dream. All this cost me a well spent £75. hope this helps and good luck.. neale ..
Also like you say, you may be running to lean, if you,ve changed from a standard airfilter to a KnN style filter or any other performance filter then this will almost certainly be the case, i was running on petrol fumes at 2000rpms when i fitted my KnN cone but you will only find this out when you put her on the rollers. Im in birmingham near the city center, there is a guy close by who is known as mr mini. Hes a honest guy and knows his stuff he charges £45 per hr £55 for 2 hrs. He did about 7 or 8 runs in the 2 hrs untill he was happy, he took my carb apart and cleaned it, replaced the needle and dashpot piston and set the carb up and she ran like a dream. All this cost me a well spent £75. hope this helps and good luck.. neale ..
bmt216a said:
Yep thats the carb.
Yeah dashpot is full as I changed the needle yesterday hoping it would sort it and refilled the dash....
Yeah dashpot is full as I changed the needle yesterday hoping it would sort it and refilled the dash....
if its a std redhot 1000cc engine it will have a HS4 with a waxstat jet fitted. its got a large (about the size of a cotton reel) alloy round thing under the carb rather than the smaller red (or black) plastic 90 deg jet tube.
these die thanks to heat of the exhaust (and can get bent through hitting the bulkhead) and will fail allowing the car to run richer than it should.
once they are knackered its impossible to set the mixture as its right until the car warms (or cools) down, the waxstat either doesnt move or moves a little and throws the mix out again.
fitting a stage one kit will make this problem worse as the changed needle will be thinner.
its a common cause of minis failing the emmissions or running like a bag of spanners thanks to the garage fiddling with the mixture to try vainly to lean it off enough.
have you also checked to make sure that the needle is correct for a stage one kit? it should be a AAU if the kit is a decent one.
a new waxstat is dear - they are about 25 quid from memory, but it may be that you need to swop it.
these die thanks to heat of the exhaust (and can get bent through hitting the bulkhead) and will fail allowing the car to run richer than it should.
once they are knackered its impossible to set the mixture as its right until the car warms (or cools) down, the waxstat either doesnt move or moves a little and throws the mix out again.
fitting a stage one kit will make this problem worse as the changed needle will be thinner.
its a common cause of minis failing the emmissions or running like a bag of spanners thanks to the garage fiddling with the mixture to try vainly to lean it off enough.
have you also checked to make sure that the needle is correct for a stage one kit? it should be a AAU if the kit is a decent one.
a new waxstat is dear - they are about 25 quid from memory, but it may be that you need to swop it.
I will have a look into that waxstat, cheers for that. Yes its a AAU needle from mini spares. Bought the stage one with the twin silencer rc40, cooper maniflow manifold and the k&n filter element.
Also will check the dashpot piston, I filled with 15/40 oil like I always have done with any other mini I had and always worked fine.
Mr mini sounds good, problem is im in Essex. will def get it tested....
Also will check the dashpot piston, I filled with 15/40 oil like I always have done with any other mini I had and always worked fine.
Mr mini sounds good, problem is im in Essex. will def get it tested....
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