[wildbill]

Hi all
Prior to the purchase of the C5 I read all info I could on better running of the R.E. C5 motor. Once I got the bike I removed the Bosch plug and replaced it with the NGK BRP6ES
The bike started and idled better but once i was on the road by about 2 or 3 miles it was breaking down and not running well. If fact the motor smelt HOT.I put up with this on the first few runs or about 10 miles. Same experience every time.So I the went back to the standard Bosch plug.Ran much better with this  bike.
Unfortunately it ran fine for about 50 miles/80 kl and yesterday when i rode the bike it was again running rough.
I took out the plug and it was Vera very black/wet. Cleaned it up then put it back in the bike. Although good it never idled as good as the NGK
Maybe the NGK BRP6ES is not suitable down under ( as the motor smelt hot) I was thinking same NGK plug but a different heat range might be the go
So any ideas in the NGK heat range - Thought about numbers 5 or 7 or 8 -  etc
I was out in my car yesterday a mazdaspeed miata. I said to the wife this cars fun but there's a lot of difference  and fun factor from a convertable to a motorcycle.
Really like this bike and the thought one day it will be completely run in and the to cruising the back roads
Thanks in advance
Regards

[GlennF]

What sort of fuel are you running ?

[wildbill]

when i bought it they had the tank filled with normal unleaded He. said after i do about 1000klm then switch to premiun umleaded

[t120rbullet]

See if the spark plug cap is screwed on to the wire properly. I've found 2 of so far that it was not screwed on correctly and was arcing between the screw and the wire.
CJ

[idk]

Why would you need to run premium fuel? That alone could make it run rich and give you those problems.

Also it will be worth checking the spark plug wire. The wire on mine came out of the plug with an ease that would have surprised a hot knife going through butter, on a really hot day.

[barenekd]

My guess would be the plug wire, too. Mine fits very loosely. It did just about come completely off giving me the symptoms you describe. As for heat ranges, the higher numbers are colder on NGKs
As for the Premium, why? If it ain't pinging, you don't need it. Actually regular will give better power than premium as it contains more gas. I can't understand the dealer's thinking.
Bare

[Arizoni]

I don't understand his thinking either.

The only thing a Premium gas has in it is more anti-knock chemicals to prevent pre-ignition in high compression engines.

With its 8.5:1 compression it would take a hell of a lot of carbon buildup to raise the compression high enough to need even a 90 octane rated gasoline.

[Desi Bike]

Here in Ontario, the gas labled "Regular Unleaded" contains up to 10% ethanol, d Mid grade fuel has up to 5%, premium up to 2.5% but generally 0%. I can also get what they call  "E85 fuel" here in town, its 85% ethanol and not worth starting a bonfire with. There is 94 octane here as well. The 94 is my choice of fuel.

[GlennF]

With aussie fuel the 95 octane is claimed to foul Enfield plugs less.

[SimonT]

I use 95 premium in mine with no issue. Thats what the dealer recommended.

[Maturin]

But why does the mule gets hickups anyway? As both plugs are getting wet it must be something different.
A tank full of bad fuel is possible, but unlikely. First to check on the list would be ignition and wiring. A bad coil could produce a similar failure pattern, and usually it's quite hard to find.
When you don't find any weaknesses in your wires I'd suggest taking it to the dealer to measure through the electrics. Probably less complicated than to look out for yourself. Hope you'll find out soon, best regards.

[Russkie]

Hi there,
My bike is a 2010 Indian domestic C5 with a short upswept exhaust.
I have a flat spot in the throttle just as you open the throttle, once you open passed that point no problem. Just rode around 1500km with it and get used to it but it is annoying. You mostly notice it when you are cruising down hill and just need to apply that little bit of throttle.
Anyhow I tried replacing the main spark plug with NGK BRP6ES and no real change. Possibly slightly less of a flat spot but could be wishful thinking.
Did I mention when the bike is hot it has an irregular uneven idle speed.

I checked Ht leads, ok. I wonder if the short muffler has caused the problem?
I note in the latest Hitchcock mail order catalogue they offer a Dynojet power commander replacement UCE for those bikes with replacement exhausts. But they need the oxygen sensor blanked off. No problem for me I mine doesn't have one.

Anyone got any idea's?

[Russkie]

Also I run 95 octane and the plug (s) a nice tan brown, it was the same when I ran 91 octane and only changed to 95 to try and eliminate the flat spot. Haven't noticed any difference with either fuel.

I also rode a 2009 UCE (with short up swept exhaust) in South India last year for about 3500km and noticed a very occasional flat spot but put it down to the dodgy fuel, but perhaps it's a C5 domestic problem.

[GlennF]

Also I run 95 octane and the plug (s) a nice tan brown, it was the same when I ran 91 octane and only changed to 95 to try and eliminate the flat spot. Haven't noticed any difference with either fuel.

I run 95 octane and I get a nice tan brown near the electrodes but the rest of the plug is very black and sooty.

If I do too many short low speed runs around town it will eventually foul up. I occasionally take an alternate longer trip to work with some highway running which seems to help.

The odd thing with my bike is the issue was not there during the low speed early run in period it arose later on well after the first service.

[Arizoni]

Russkie

It's pretty hard for most of us to figure out because we are running the O2 sensor models over here and they have a totally different computer mapping.

A few months ago in India Royal Enfield came up with a reprogrammed map for their Non- O2 computers.
It has to be installed by a dealer but it is just a simple plug-in to reprogram the bikes computer.

Have you had this new program installed yet?  If not, check with your dealer to see if it is available.