MRC Forum- brought to you by www.morini-riders-club.com

What plug caps are the panel using this season?
I know that my mate, the previous owner of my 3.5 Sport, had been having starting dfficulties and had replaced the ignition transducers, but I reckon I have uncovered the real problem during its overhaul - the short-reach plugs would have efficiently hidden the spark from the fuel wouldn't they?
That's going to be remedied, though I will run a well greased plug tap down the threads to remove any carbon that may be lurking down there. He'd also replaced the plug caps with NGK SB05F ones. My previous experience with British magnetos suggests that a non-resistor plug cap would be preferable along with copper cored HT leads.
I found a reference on this forum to removing the resistor from the NGK job but so far Ive not found a way that it can be done. Similarly my search for a similar cap even with a 1 ohm resistance has revealed that they are available in Spain, but for collection only
Any suggestions gratefully received.

Steve

I use NGK BP6ES plugs, with straight-through plug caps (ie no resistor). You should be able to get both from The Green Spark Plug Company.

Thanks, Ming.
The ones that were in are actually 1/2" reach B6HS I've got some BP7ES on the way. I'll see how it runs with those first. I have looked at the GSPC site but they have only the resistor type straight caps. I tried pressing the centre out of the NGK one but it wasn't willing to budge. They're well made, I'll give 'em that much!
If all else fails then I can make some up with parts from Vehicle Wiring Products. It would've been nice to have 'properly' made ones like the NGK though.

Steve

Not as bad as the other way round - though you would find out very quickly.

I run resistor plugs (EIX) and NGK resistor caps. No problems, but that's with an NLM module and conventional coils.

Someone converted some NGK to non-resistor caps a couple of years ago.

viewtopic.php?f=5&t=4024&hilit=non+resistor+caps

For standard setup. UK normal road riding. Genuine NGK BP7ES + NGK straight resistor caps + copper cored HT lead. Gap 0.7mm . Tested over decades.
The NGK BP7EV (EVX) variant is no longer available.
Mark

I agree...

Thanks chaps.
I guess I'll be giving the caps I have a try then to see how we get on I 'm counting on having the correct plugs to give the biggest imrovement.

Steve

A member here made some up that were the business.
http://www.morini-riders-club.com/foru ... f=5&t=4024

DD

Is the resistor there for noise suppression purposes? If so running without one may cause interference to people's cat's whisker... I thought you ran either resistor plug cap or resistor plug but not both. Still, if it works...

The project Sport has straight leads with a rubber cover and Bosch spark plugs...

Think I'll be changing them!

I read somewhere that the overall resistance of an NGK BPR n EIX is less than an NGK BP n ES - but I can't find it again. The resistor in the cap is for 'suppression' of radio/TV wavelength emissions AFAIK.

An iridium resistor plug with an NGK resistor cap seems fine on both mine. Then both have conventional coils (small scooter ones on the road bike and larger XV250 conventional ones on the hill climber), so perhaps they produce a fatter spark that can cope? I also treated them both to brand new nice rubbery copper cored HT leads from http://www.sparkplugs.co.uk to go with the new caps. OEM transducers and ratty old leads with R plugs and ohm caps might be another story, but for me it's a case of "if it works..."

I had to change the EIX plugs on my MX5 this year as it was getting a bit lumpy on a cold start, Mustn't grumble as they had been in there for nearly 20000 miles.

72degrees wrote: The resistor in the cap is for 'suppression' of radio/TV wavelength emissions AFAIK.

Ah, that brings back memories How many times did Saturday Night at the London Palladium or the Black and White Minstrel Show disappear into a snowstorm as someone rode by on his James Comet or BSA Bantam on his way to the pub?
I seem to recall that it was actually illegal to use any sort of engine that wasn't fitted with suppression to prevent interference to TV and wireless broadcasts. Whether anyone was ever prosecuted, who knows?

Thanks for all the suggestions, guys. I'm going to go down the 'path of least resistance' as it were (sorry!) and get some non-resistor plug leads/caps sorted out, at least until I've ironed out any other potential faults over the coming miles. The bike has been fitted with new looking blue transducers, which I think are Lambretta ones, aren't they? They seem to get the thumbs up on the Dutch site from what I can see.
Initial trials with the new BP7ES look favourable - even with the cleaned out carbs roughly set up by eye, she can be started easily on the kickstart by hand on the workbench Try doing that trick with a Matchless 500 single! Over the next day or two I'll get the bike run up to temperature and change the oil and set up the carbs properly.
It'll then be a question of working my way through the wiring - I see that's where the idea for spaghetti came from
On the plus side, my membership details arrived this morning and I've already been looking at the coloured wiring diagrams which help to make things much clearer.

Steve

Can anybody give a 'condensor'd' version of this thread? AFAIK = as Farad I know? Watt am I on about? Ok, the taxi is here, I'm off ohm...

MickeyMoto wrote:Can anybody give a 'condensor'd' version of this thread? AFAIK = as Farad I know? Watt am I on about? Ok, the taxi is here, I'm off ohm...

He's here all week, folks!

Steve

I use these:

https://www.z1enterprises.com/dyna-igni ... black.html

Just by way of an update, I found these on ebay -

https://www.ebay.co.uk/itm/HT-Lead-Crim ... 2749.l2649

Not the sort of tool that would last a lifetime but for crimping the odd HT lead, they are well up to the task and significantly cheaper than the bespoke tools available in the UK. The remaining bits - HT lead, rubber caps and terminals - I got from Vehicle Wiring Products. There was a time when I would've gone for the proper tool, but having now reached the age where buying green bananas is a gamble I'm a little more circumspect

Steve