Hey guys,

Just re-furbed a 1.5" SU to put on my 1098 and I need a bit of needle guidance.

Currently has a ADF needle, and was recommended and ABP needle. Does this seem like the correct needle? The end seems to be different to the ADF. which doesn't seem to have a "flared" end on it.

As far as I know, Standard engine, only mods will be the carb on a lynx manifold, with maniflow LCB extractors and a Ramflo air filter.

I plugged the 2 needles into that comparing graph thing and the ADF is a richer needle. Would it still run?

Thanks in advance. Tuning is new to me, im used to having an ECU do all the work for me

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I have a problem.. apparently

What size is the motor? There is a book on modding the a series engine and has everything u need in it. It has a chart which you can go to and find the exact spring and needle you need and with what engine specs work with it

Here's a pic

ADF and ABP needles are both spring loaded for later, HIF SUs. For the earlier, straight needles in HS4s, the factory recommendation for 1098cc Mini Autos (which used an HS4 single carb) was a DL needle, very close in profile to your ADF. Either ADF or DL should be a good starting point. I think DL needles require a small adaptor kit to fit fixed needles to a spring-loaded carb.
It is usually pointed out that most of the end stations of the needle profile, after about 7 or 8, are never used, as the carb piston does not need to rise that far to supply the engine.
Please make sure your Ramflo air filter is oil-soaked and not run dry. Otherwise it will not filter out damaging grit from your engine. Don't ask how I know this.
Consider any kind of paper filter in preference!!!

Thanks for the input, Guys.

I have had more luck with the ADF needle, but it still isn't great. There's a large flat spot from the lower end of the rev range most of the way up.

I tried a couple of different springs and tomorrow I will try different oil in the dash pot.

I'm a bit over my head at this stage, but hopefully I get there

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I have a problem.. apparently

are you tuning it right?

I found a CP4 needle works well in a single HS4 on a 1098. With a sports filter on.

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

Probably not. I have tried to get the idle tune as good as I can without a colortune or a sniffer. And I think it's close but probably isn't perfect.


Cp4 looks a fair bit richer than an ADF. May be worth a try. These needles add up when you have to buy them!

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I have a problem.. apparently

No 6 or no 7 work too.

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

Where's the cheapest place to get needles from? Postage kills me. I wish mini king didn't move

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I have a problem.. apparently

Karcraft has AH2, E3, M, and #6. Prices from $15 up. But the #6 is ~$28, I dunno why.
You could also try SU Midel.

[edit] I have a spare CP4 here you can have cheap.

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

Thanks mate, I'll let you know. May just swing to midel tomorrow. Was hoping to get to the mitg show

I did a few tests of different dash pot oil. Even no oil. Resulted in the same behaviour each time.

Hold accelerator in a spot. It will bog down and then gradually climb up to stronger revs.

Car was running fine beforehand but could it be spark or timing related? I was considering trying a full tune up but I fear I may make it worse with my limited knowledge :p

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I have a problem.. apparently