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[MartinB]

Has anyone experimented with different grades of spark plug?I'm running our host's Amal kit but am finding it hard to start the engine and under some conditions ie going up a very steep hill it just doesn't feel right.

[Mark M]

Martin, it's probably not the plug. You need to do a plug chop to be sure, that is, kill the engine when well warmed up and under load and then check plug colour. Hard starting is *probably* unrelated, can you give more info on how you do get it running?
REgards, Mark

[MartinB]

Mark

It seems to over-fuel on starting.

I can't use the electric start at the moment due to ongoing sprag problems which are being investigated.It could be my technique as i've had over 35 years of reliable mostly electric start Jap bikes.Sometimes it goes first kick but at others it's really difficult,kicking back and spitting through the carb.The de-compressor seems to have no effect nor does the choke lever.I always tickle the carb from cold.

I guess as you say i'll need to do a plug chop for the running problem.I've chaged the main jet a few times and although it's a bit better on the flat now as i said it seems to struggle up a steep slow hill.

[Mark M]

Martin, that's helpful but contradictory! Spitting through carb is weakness, if overfueling at start you'd get a stuttering lumpy engine note and black smoke from exhaust. Try using choke only and not tickling, and if that doesn't make a difference choke and no tickle, etc. In summary I think your start technique may not be quite right. The choke should definitely do something if working properly! Finally, you may be right about main jet, what settings are you using, slide, main jet and pilot? Lastly, do remember to use the gearbox, these engines are not long stroke sloggers by Brit bike standards, and need to have reasonable revs to progress!
REgards, Mark

[MartinB]

Thanks Mark.Sorry to confound you but that's how the symptoms appear!I can't remember the carb settings but only the main jet has been changed since receiving the kit from our hosts and i think that is now back to their standard size for the S and B filter,Mr H's less restrictive exhaust and silencer,removed PAV etc.I don't tend to let the engine slog as i'm used to free-er reving Jap engines.

[Norm]

Martin fuel problem not the plug

[MartinB]

OK-it's just that a knowledgeable mate has suggested a change of plug grade.I'm not too impressed with the Amal.My bike ran better ,started easily and was much more fuel efficient with the old Mikuni CV.

[Craig]

Hello Martin,
I Run a 350 AVL with a Amal mono block carb,.(Ok Electra slimier) ..One Expert Pre Me, Had fitted the 500 Plug To tune it? so perhaps it works both ways??. But going on NGK's India website I got the correct Plug...And after adjusting the Neddle hight all is well.
So Only advice is Try The INDIAN Spark Plug sites its all in English and they have been running them longer than us too....

[Ian M Brown]

Martin, I had to change main jet to a 220,(std 200) slide to a no 3(std no4) and lift the needle one notch before mine was right !

[MartinB]

Thanks for the posts.Looks like a lot more fettling is required then.