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Kangaroo jumping

paul.hebert@sky.com's picture
Submitted by [email protected] on 9th Aug 2020 - 07:11

Can anyone help me. I have a Stigma 1.6 150 H.P engine in my caterham  and anything below 3000 r.p.m the car kangaroo jumps and the only way to stop it ,is to dip the clutch. I find it very difficult either driving through towns or in traffic. I have just had the carbs balanced but that has not stopped the jumping.

Comments

K7 VCT's picture
Submitted by K7 VCT on 9th Aug 2020 - 10:06
Hi, presume you mean throttle bodies, no carbs. I understand the 150 sigma is well know to run poorly on occasions, but yours must be something else, where are you based

Orange is my new black

Ballistic orange 310s
paul.hebert@sky.com's picture
Submitted by [email protected] on 9th Aug 2020 - 13:40

I am in East Sussex, small town called Uckfield.

K7 VCT's picture
Submitted by K7 VCT on 9th Aug 2020 - 17:58
Perhaps call up sevens and classics for help

Orange is my new black

Ballistic orange 310s
John Wragg's picture
Submitted by John Wragg on 30th Aug 2020 - 12:24

I have the same problem with my Sigma 125 engine. Just learned to manage it. I'd be interested in how you get on.

sprocket's picture
Submitted by sprocket on 14th Sep 2020 - 16:25

Hi, Same problem with a 2012 140hp Supersport. I was advised by someone who'd built a Blackbird powered 7 which had a ridiculously light throttle spring to increase the spring tension. I added another coil spring to the top of the throttle pedal and bingo, it reduced the kangarooing quite a bit. It's still there which you have to manage but it's much improved.