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[DannyDan]

Hey, my second post on here. A big thanks to the folks that helped me out with my first!
My '84 350 is losing a load of power in the hills. As mentioned in my first post I live in Nepal, that famously mountainous country! So this is a real pain whenever I'm out for a ride further than the local town, and pretty much takes all the enjoyment out of the ride. I'm seeing 125cc scooters nip past as I struggle up a hill in 1st or 2nd feeling like I'm doing serious damage to the bike at the same time. Then after 10-15 mins up a steep hill the bike will just often just cut out, I guess due to heat?
The bike will rev out way higher than I want to run in one gear, so I shift up and there is no power there so I'm forced to shift back down and either crawl along or rev the nuts off the engine.

I'm pretty sure the ignition timing is good. I have the Top Dead Centre tool and feeler gauge from Hitchcocks and have meticulously set it myself while the bike is static. Although I now don't use the feeler gauge. Found it idles better with a larger gap than .4mm
Brakes aren't dragging at all.
Bike starts and idles pretty much fine.
Have fitted a new RE carb and K&N replica air filter. Uprated jets as per Hitchcocks recommendations. The problem was the same before these were fitted.
Fuel flow is fine.

Advice on what the causes of this might be and how I could go about remedying them would restore the joy to my Enfield ownership!

[PeteF]

Danny, what's the performance like on the flat?

[Revband]

There may be a clue in "it idles better with a gap bigger than .4mm" a bigger gap will advance the ignition slightly, so possibly despite your good efforts the ignition is probably too far retarded.

[DannyDan]

Hi Pete. The performance seems pretty decent, without passenger anyway. Although it is pretty sluggish taking off from standstill. And it does feel like I have to rev it quite high to get the power from it. Hard to know though. I don't have an equivalent bullet to compare it to. I can try to find one though. The problem here is that because the mechanics are so terrible it's hard to know what an old machine should actually run like!

[DannyDan]

Ah ok, thanks for the tip Revband. I'l re-check the timing then. I had also heard of doing 'ping' timing after setting the points static but i really don't understand that and there's no mention of it on the Hitchcock's timing setting guide. I really got confused by the part about how to check the full advance setting on that article as well............................................................ "To check the full advance timing position, mark the top
dead centre tool with the advance setting above the TDC
mark. Turn the engine back, then forwards until the piston
reaches this new mark. Now turn on the ignition and
carefully with your fingers, rotate the points cam
clockwise, against the pressure of the springs. If
everything is correct, you will hear the snap as the points
open exactly as you reach the limit of the travel, and the
ammeter will flick back to the centre"............................. Wouldn't the points already be open at this stage if the timing is set correctly and the points fire at the higher mark that indicates .8mm before TDC? .... I have fitted a whole new points/backplate/condenser/spring cam set so these shouldn't be worn out anyways...

[DannyDan]

Quick thought... Does anyone have an idea of what size modern bike would have equivalent power to a properly sorted bullet? There are a whole lot of sporty-ish modern bikes here of 150, 180, 200 & 220cc

[ed.lazda]

• How many miles has it done, and how good is the compression when you kick it over? Maybe worn cylinder internals.
• Valve clearances?
• Brakes binding?
• Blocked air filter?
• Carburettor jetted properly for the altitude?

(Amongst other things)

[ed.lazda]

PS my Bullet 350 will chug along happily at about 65 mph (indicated) on the flat, and will get up to 70-and-a-bit if asked nicely.

[ric]

The higher you go the less air there is, the smaller main jet you need to compensate which results in a lower (than sea level) power output.
AT 4,500? feet you're probably around 15% down on power compared to using the bike at sea level. How high are these hills above Nepal?
High enough to feel even more power dropping away as a result of atmospheric change? The best you can hope for is to keep your bike running at its optimum. I've personally found the TDC tool very hit and miss, I think the closest I managed was within 10* of TDC, a friend who came round to have his electronic ignition set up by me using a timing disc and strobe managed to get it as close as 15*


if you're wondering why your being overtaken by smaller bikes... A 200cc KTM will has a far higher power to weight ratio than a 350 bullet. A Zig Wheel comparison gives the KTM a 5hp advantage over a modern 350 bullet and the KTM weighs 44kgs less. The KTM has the advantage of a modern electronic fuel injection system which automatically compensates for any altitude changes. Ironically fuel consumption is not that dissimilar between both bikes despite the KTM having 25% more power than the Enfield.

[stinkwheel]

Shouldn't be cutting out. However, also mind your expectations. A standard 350 bullet will be making what? Maybe 14bhp? There is every chance these scooters have as much if not more power than your bike. I was riding with a friend on a BSA B40 (a late 1960's 350 single which is in many ways, more sophisticated than a Bullet) on a motorway last month and we were both overtaken by someone on a honda C90 when we hit a head wind.



My 350 Bullet will easily drop to 40mph if going up a steep hill on a properly surfaced UK road. Especially if there is a head wind. I generally think of it as having roughly the same power output as a 125cc bike.



I think however, from your description of it cutting out when hot, there is a risk you have repeatedly heat-seized the engine. It may well be a good plan to strip the top end to inspect the state of the piston and bore.



Since you're in Nepal, what sort of altitude are you at? Very high altitudes could well cause issues.