Unofficial Royal Enfield Community Forum

Royal Enfield Motorcycles => Bullet Iron Barrel => Topic started by: jacobia stig on April 18, 2018, 12:26:37 am

Title: Does everyone who runs a enfield bullet iron barrel...
Post by: jacobia stig on April 18, 2018, 12:26:37 am
... also have another bike that just works fine for longer than a couple of months at a time...

 my 92 500cc bullet is my everyday bike for the last 2years and I love what it is, where it came from and everything it's related too. Ha! BUT! I swear, if it wasn't for some of the incredible indepth knowledge  and articulate and open ways of communicating over these thousands of pages of priceless info, there would be a lovely old thumper in the river Mersey by now :)

I'm really thankful this forum and all your brains exist.
I'm not even gonna trouble anyone with my latest bullet bullshit in detail, I just search through and sure enough the answer lays deep within this sacred single place. 
Title: Re: Does everyone who runs a enfield bullet iron barrel...
Post by: mrunderhill1975a on April 18, 2018, 12:55:53 am
My '99 has never left me stranded, even when the battery wire rubbed on the cover, shorted out and my legs were smoking. Keep oil in it, keep it under 55mph, tighten loose bolts once a week and it seems to run forever, it has over 32000 mile on the clock.
Title: Re: Does everyone who runs a enfield bullet iron barrel...
Post by: Stanley on April 19, 2018, 05:54:12 pm
When I sold my Ducatis and bought my iron barrel, the plan was to buy a reliable backup like a Guzzi. The Bullet's been so reliable, it may become the backup to something more troublesome.
Title: Re: Does everyone who runs a enfield bullet iron barrel...
Post by: Kevin Mahoney on April 19, 2018, 06:51:22 pm
Stanley - The iron barrel's are great bikes but..... at some point you will have trouble. Probably something small but it will happen.
Title: Re: Does everyone who runs a enfield bullet iron barrel...
Post by: Bilgemaster on April 19, 2018, 10:37:02 pm
I've had my 2005 "iron belly" since December. It hasn't been without its share of "getting to know each other" issues, though I'd gathered anyhow that the reason I got it for so little was that the previous owner was not really the tinkering sort. Enfields clearly ain't for everyone. Fortunately, I've at least nursed along a whole parade of quirky old British iron and other well-worn jalopies and resurrected hoopties in my day, so am at least semi-prepared for dealing with my new-to-me Enfield's moods and foibles. It's not really my "daily driver", being purely a recreational ride, so I guess that helps. Still, I've taken the precaution of arranging for 100 miles of free towing (expandable to 200) in case of breakdown through our American Automobile Association (AAA), which offers an extra RV rider to its regular auto AAA Plus service that also covers bikes. Decades ago in Britain I enjoyed a similar service through your Royal Automobile Club (RAC) for the "quirky" old ex-police Norton Commando I owned back then, and if it's still available, you might do well to get that service for your Enfield.

Personally, I'd enjoy reading details of all you've had to deal with in your own "iron belly", if only to learn what I might want to keep an eye on in mine. As for mine thus far, the later style silly crankcase breather and catch can setup (which your '90s one may well mercifully lack) was clogging up, and has been pitched in favor of a simple hose and KrankVent style checkvalve (https://forum.classicmotorworks.com/index.php/topic,25940.msg298895.html#msg298895), and I've broken the shabby original clutch cable, since replaced with a superb quality Barnett one (https://forum.classicmotorworks.com/index.php/topic,25968.msg299048.html#msg299048). I feel it may be fairly well "sorted" for now. Hoping it is anyhow...
Title: Re: Does everyone who runs a enfield bullet iron barrel...
Post by: ace.cafe on April 20, 2018, 12:54:25 pm
Most of the needs are maintenance.  There are some internal engine weaknesses, but if you ride below 5000 rpm and above 3000 rpm, it should be okay.  Don't lug it, don't rev it too high.
Title: Re: Does everyone who runs a enfield bullet iron barrel...
Post by: Bilgemaster on April 20, 2018, 03:33:02 pm
Most of the needs are maintenance.  There are some internal engine weaknesses, but if you ride below 5000 rpm and above 3000 rpm, it should be okay.  Don't lug it, don't rev it too high.

Yeah...I'm probably guilty of lugging it just a bit on the hills--nothing too far down in the trenches, but I do tend to ride a little too "over-gently." Just out of curiosity, lacking a tachometer and all (though not really missing one), roughly what might 3,000 and 5,000 RPM correspond to in miles per hour in top gear on a 5-speed gearbox cast iron assuming standard engine and drive sprockets? Anyone know offhand? Is there a particular "sweet spot" speedwise for longer range cruising? Mine seems to like it well enough just a hair under 60 mph (indicated), depending on terrain, but maybe that's pushing her just a bit too hard longterm?
Title: Re: Does everyone who runs a enfield bullet iron barrel...
Post by: ace.cafe on April 20, 2018, 04:18:51 pm
5000 rpm in top gear is top speed, ~80mph. This should only be for momentary use, like passing. With a std cast iron barrel, I recommend cruising no faster than 4000 rpm (64mph), and it likes it more when cruising at 3500 rpm (56mph). 3000 rpm is about 48 mph in top gear. The engine will tolerate 3000 rpm on flats, but it tends to drop when encounterin grades. The 5-speed has a nice 4th gear to deal with that, but the 4-speed has a huge ratio gap between 3rd and top, and this causes problems with proper gear selection in certain situations.

If you have changed to an alloy barrel, it is a bit more forgiving because it cools better.
Title: Re: Does everyone who runs a enfield bullet iron barrel...
Post by: Bilgemaster on April 20, 2018, 06:39:37 pm
5000 rpm in top gear is top speed, ~80mph. This should only be for momentary use, like passing. With a std cast iron barrel, I recommend cruising no faster than 4000 rpm (64mph), and it likes it more when cruising at 3500 rpm (56mph). 3000 rpm is about 48 mph in top gear. The engine will tolerate 3000 rpm on flats, but it tends to drop when encountering  grades. The 5-speed has a nice 4th gear to deal with that, but the 4-speed has a huge ratio gap between 3rd and top, and this causes problems with proper gear selection in certain situations.

If you have changed to an alloy barrel, it is a bit more forgiving because it cools better.

Thanks! Good info. I've never had mine faster than maybe 62 or thereabouts passing, and am highly unlikely to ever broach 70 even short term, let alone anything close to 80. Looks like I'll be plodding on up to that shindig in Pennsylvania in June in the mid-high 50s, and I'm perfectly OK with that.
Title: Re: Does everyone who runs a enfield bullet iron barrel...
Post by: Stanley on April 20, 2018, 06:48:29 pm
Ace, that seems to match what my bike prefers. I've had issues but nothing my older Brit bikes didin't do, dropping the horn, sidestand and tail light until loctite saved the day. I may be paranoid, but I replaced that slotted piston for peace of mind.

Title: Re: Does everyone who runs a enfield bullet iron barrel...
Post by: Bilgemaster on April 21, 2018, 04:34:26 am
Ace, that seems to match what my bike prefers. I've had issues but nothing my older Brit bikes didin't do, dropping the horn, sidestand and tail light until loctite saved the day. I may be paranoid, but I replaced that slotted piston for peace of mind.

Not to take this thread off-road, but what could you expound a bit on the "slotted piston" you mention, why it may be undesirable, and what exactly you replaced it with? I find nothing in the forum archives specifically mentioning "slotted piston"...something about a highly regarded "ACE piston" though. Thanx!
Title: Re: Does everyone who runs a enfield bullet iron barrel...
Post by: ace.cafe on April 21, 2018, 03:29:54 pm
Not to take this thread off-road, but what could you expound a bit on the "slotted piston" you mention, why it may be undesirable, and what exactly you replaced it with? I find nothing in the forum archives specifically mentioning "slotted piston"...something about a highly regarded "ACE piston" though. Thanx!
The factory piston is known for separating in two just above the gudgeon pin boss. To be fair, it is not totally the fault of the piston, but when the causative conditions occur,  the piston does not survive.  The ensuing carnage results in a full engine rebuild.

Basically,  the engine is built with such low power output that most of the fuel energy is dissipated as heat instead of power to the crank. Increasing the power in such a way as we have outlined on this forum uses the fuel more efficiently, and thus gives more power output with about the same fuel consumption.   The engine does not suffer nearly as much from overheating, and is a lot more fun to ride, and can go long terms at interstate speeds. The usefulness of the bike is greatly increased.

However, the inherent weaknesses in the factory build need to be overcome to attain reliability in the higher state of tune, so at the very least,  the piston and con rod need upgrading, and a high quality crank rebuild  done to make sure that it runs true for least vibration.
Title: Re: Does everyone who runs a enfield bullet iron barrel...
Post by: Stanley on April 21, 2018, 04:54:58 pm
Here's a photo of the stock piston showing the slot feature.
https://image.ibb.co/hqLa9H/IMGP0288.jpg
Title: Re: Does everyone who runs a enfield bullet iron barrel...
Post by: ace.cafe on April 21, 2018, 05:50:54 pm
Here's a photo of the stock piston showing the slot feature.
https://image.ibb.co/hqLa9H/IMGP0288.jpg

Very illustrative photo!


To further clarify my post above, it's the heat that causes these failures.
Excessive heat causes rapid onset of detonation, due to preheating of the incoming mixture. When detonation, or pre-ignition occurs, the protective air boundary layer on top of the piston is blown away, and the alloy is exposed directly to the combustion temperature,  which it cannot stand for long.  It absorbs too much heat, expands beyond the clearance in the cylinder, and rubs the walls. This pushes any remaining oil away, and it seizes. If you are lucky, it only mini-seizes, and you stop for a little while,  and it will start back up again. This doesn't mean that nothing is damaged, but merely that the damage was somewhat minor. That's if you are lucky.
If you are not lucky, the piston will separate, and the engine will beat it's internal parts  with the loose con rod. If the con rod breaks instead, which is also common, then the stub of the broken con rod will flail around inside the engine case, knocking big holes in it, and engine parts and oil ejecting all over the road.

This happens most commonly when riding at low rpms, encountering a hill, and lugging up the hill in top gear, thinking everything is fine.  The pinging begins, the piston heats up, and.....BANG. The engine comes apart. I have engine cases here with holes in them from exactly that.

That is why the rpms need to stay in the "happy" range that I stated previously.  Use the gearbox.
Title: Re: Does everyone who runs a enfield bullet iron barrel...
Post by: jacobia stig on April 26, 2018, 01:48:43 am
i love this forum :)
i need to do the piston swap asap really, ive enjoyed jetting it up for a few months at a time  every now and then because it really does become alot more fun to ride and everything works really nice together... but it gets hot, and sooner or later i melt the inlet from the carb i jet back down for abit and go back to tootling about... i was just having a moan while i waited for bits to arrive and the sun was out withot me.

but ya see, when i do the piston swap, then ill do other bits while im in there and hence my original gripe... simply put.. i need 2.

there's a weird thing on ebay called a trifield at the moment.. it looks a mess.. i really want it.
Title: Re: Does everyone who runs a enfield bullet iron barrel...
Post by: Adrian II on April 26, 2018, 03:59:48 am
The Trifield (unit 350 or 500 Triumph twin in RE Crusader frame) was quite a popular special in the UK back in the day. You can still get the engine plates to build one from Unity Equipe.

Quote
it looks a mess..

This one?  ;D

(https://i.ebayimg.com/images/g/DM0AAOSwwBha12Je/s-l1600.jpg)

Er... yeah, home-brew build quality varied enormously! One important job was to find a separate oil tank that was a decent fit, the Crusader oil tank was intergral with the engine and gearbox. If it is this one it also has RE's own leading link forks.

Feeling brave?

A.
Title: Re: Does everyone who runs a enfield bullet iron barrel...
Post by: banjelele on September 19, 2018, 05:13:38 am
To answer the original question my 350 bullet was my daily driver for about 8 years. I had moved to a new unexplored part of the province and spent my summers exploring every backroad and trail I could find. These machines are pretty good on back country excursions. Admittedly I got even further back into no man's land once I got a 1975 Yamaha 125 enduro but I certainly found all kinds of adventure on my Bullet.
Title: Re: Does everyone who runs a enfield bullet iron barrel...
Post by: cyrusb on September 19, 2018, 03:24:18 pm
Answer to original question: Yes, I have a Ducati also. But I use it only when I need to go faster than 55,(out with the boys, following grandma to the doctors, etc.) I can however, understand your opinion. Coexisting with a bullet Original is somewhat of a lifestyle. The successful Original Bullet operator will invariably have many of these traits listed here: 1:More hair in ears than on head  2: Waist of trousers under armpits 3: Toenails the color of school buses 4: Constant search for restrooms  5: Nosehair suitable for braiding(thx Bilgemaster) 6:The term "your growth" refers to that thing on your back.etc. Soo Where do you stand ?
Title: Re: Does everyone who runs a enfield bullet iron barrel...
Post by: heloego on September 19, 2018, 03:36:10 pm
I, for one, do not have more hair in my ears than on my head.  ;)
Title: Re: Does everyone who runs a enfield bullet iron barrel...
Post by: cyrusb on September 19, 2018, 03:44:06 pm
I, for one, do not have more hair in my ears than on my head.  ;)
You also do not have an Original Bullet , but I suspect there is one in your future ;D
Title: Re: Does everyone who runs a enfield bullet iron barrel...
Post by: heloego on September 19, 2018, 03:45:23 pm
I may have to drop the pants waist down a bit from my armpits before that happens.  :)
Title: Re: Does everyone who runs a enfield bullet iron barrel...
Post by: AgentX on September 20, 2018, 04:33:02 am
Most of the needs are maintenance.  There are some internal engine weaknesses, but if you ride below 5000 rpm and above 3000 rpm, it should be okay.  Don't lug it, don't rev it too high.

Oh, I wish.

Title: Re: Does everyone who runs a enfield bullet iron barrel...
Post by: Bilgemaster on September 20, 2018, 07:49:07 am
My hat's off to you, cyrusb. Your description of "following grandma to the doctors"  as characterizing those outer limits beyond an "iron belly" Bullet's performance is the finest description that has ever been penned, or perhaps ever will be. As for your other descriptions of the common characteristics of successful old school Bullet operators, you seem to have overlooked that resplendent nosehair suitable for braiding.
Title: Re: Does everyone who runs a enfield bullet iron barrel...
Post by: cyrusb on September 20, 2018, 12:00:49 pm
Bilgemaster, That is perfect! Let "Resplendent nosehair suitable for braiding" be #5. 
Title: Re: Does everyone who runs a enfield bullet iron barrel...
Post by: longstrokeclassic on September 20, 2018, 06:08:50 pm
I run an EFI with a carb fitted, whilst it's not an iron barrel model it has everything I wanted my last Iron barrel model to have - stronger crank, steel con rod, (very) high capacity oil pumps, pushrods that don't need regular adjustment etc etc etc.
Now it has a carb fitted if it wasn't my only bike I'd have no hesitation in having it as an only bike. The feel of the engine with a carb has a more authentic feel to it.