[Bala2014]

We are still here in Kyrgyzstan with 13,000 kilometers to go and just realized that my low-power/overheating problem I have been having for a while has not been solved and could be detrimental to the continuation of our trip if I cant sort it out.  This is a long write-up so bear with me, I want to make sure I include all relevant clues/details to diagnose.

(Reminder...the bike is a 2006 500cc Bullet standard)

So, the problem started after I rebuilt the engine in Delhi.  We set off towards nepal, and the first bit of hills we encountered she began to lose power...the gradual hills in 3rd or 4th gear there was a rattling in the engine and loss of power, then when the hills got more steep she really lost power till she could only move up in 2nd sometimes first gear.  I realized she was overheating and after letting her cool a bit she would do better, but still not so good.  This problem persisted for several weeks in Nepal and back into India...we didnt try and do any big mountains but even in lowland areas any sort of hill would have her panting.  So back in Delhi we had very little time before we had to leave India, I told my mechanics there about the problem and they assured me it was a timing or possibly carb issue.  They adjusted the timing and took off the K&N filter I had on to replace with the old model air filter and re-adjusted my carburetor.  There are no hills in Delhi and since the problem only came on hills and we were short on time there was no way to test if it was fixed but my mechanics were pretty confident so off we went to kyrgystan. 

Well, just tried our first big mountain pass and major loss of power at the first sign of a hill.  I think the loss of power is the first issue...and that causes some overheating. Because even when the engine is still cool she doesnt perform up the hills, (better than when she has been trying for a while but still not like she should). 

So something changed since this rebuild.  So, what did we do there? 

New valves and seats
New engine bearings
Reconditioned crank
Points plate
New electrical
New piston rings (piston looked ok and had just been replaced 3000 miles prior)
New Carbuerator (replaced MikCarb V28 with new of the same)
And a bunch of other stuff not so relevant (brakes, wheel bearings, tires, etc.)

I did a pretty decent break-in before reaching nepal although certainly not "To the 'T'"

Is she just overloaded?  Dont think so.  We do have some extra spares and camping gear now that we didnt before but she never had this problem in the 3000 miles i did with her through india before the rebuild.  Not to mention I have a friend who drove a 350cc even more weighed down than me from India to London and he had no issues.

What I have done to troubleshoot/try and solve this myself:  I tried checking the timing myself, using the method in the Snidal Manual of putting a pencil in the spark plug hole etc.  Im no pro and this was my first attempt but I tried it twice and think I have it set pretty good...still problem persists.  (PS there is no rattling/ping going up the hills, just loss of power).  I moved onto carb.  I tried putting the old carbuerator on, the one I used before the engine rebuild which had no issues (I carried it will me as a spare)...still problem persisted.  I tried some adjustments, cleaned it, did spark plug tests for proper coloration, got it to where I THINK its ok but still problem persists. 

So...I'm not ruling out the possibility it is still a timing and/or carb issue, Im new at this stuff and the tinkering I have done may not have have been so precision.  But Im wondering if maybe the new piston rings didnt seat? or one of the new valves?  We will be in Osh, a decent sized city in a few days (Assuming we can make it through the mountain pass!).  We heard there is a Swiss company there offering moto tours with a proper garage so we are going to try and get friendly with them (my girlfriend/pillon is Swiss).  I would like to test the compression there if they have the gadget.  But problem is we are on a strict time budget.  We have date sensitive visas lined up for several countries and if we have to have some part mailed to us in Osh we will be cutting it very close.  So I wanted to PLEASE PLEASE beg for all your support and ideas as I try and solve this issue.  I will update more when we get to Osh and have their mechanics look at some things and hopefully get the compression tested. I can even take some pictures of things you might want to see and upload those 

Thanks in advance for your consideration.  Really HUGELY appreciated.  I can also be reached by skype is someone wants to chat that way Skypename: jordan.m.jones

Thanks all and greetings from the other side of the world.

Jordan, Magdalena, & Bala

[Arizoni]

I can only think of two things that might be contributing to the problem.

Is it possible that a baffle in the silencer has become dislodged and is blocking the exhaust flow?

Less likely but another possibility:
As you completely rebuilt the engine is it possible the dots on the cam gears weren't aligned properly?
If either gear was misaligned when it was assembled it could reduce the engines torque output.
Attached is a photo of the Iron Barrel Repair Manual showing the two marks on the crankshaft gear (pinion) aligned with the two marks on the exhaust cam gear (pinion) while the one mark on the inlet cam gear (pinion) is aligned with the one dot on the exhaust gear.  This all happens when the crankshaft key is at 12:00 and the piston is at top dead center.

[c1skout]

I would guess your timing is still out some. The method in the Snidal manual that you reference is to set the static timing. You still need to fiddle with it a bit more. I live on a hill so it's easy for me, I leave the points cover off and run up the hill, if it's not right I pull off and advance or retard the timing at the points plate until it sounds good, no pinging at low speed and pulls crisply. I only need to do this after I set the point gap. I hope that's all it is for you.

[jedaks]

What octane rating of petrol are you able to get? If you have a higher compression piston you need higher octane.

[potboiler]

Dear Bala
What struck a chord with me was that you said you replaced the points plate. When I took off my points plate this week I was shocked to see the state of the back of it!! For 10 years and 5000 miles the advance/retard weights had been rubbing against the plate and condenser (they had actually ground away 1mm of metal from the condenser!!). For some stupid reason Enfield make the condenser sit in a cut-out in the plate which allows it to protrude through into the path of the rotating advance weights. So, the advance  mechanism had probably never adjusted the ignition properly from day one as the weights could not move freely or return to there static setting.
You can quickly and easily check to see if this is your problem. Just remove the points cover. No need to interfere with the points or timing, just unscrew the condenser and see if there are any rubbing marks on the back of it. If there are, then you simply need to bend the condenser bracket a little to give it some clearance from the rotating advance weights, or put a few small packing washers under it's mounting bracket. Although you checked that the static timing was correct, if the advance weights are stuck or preventing from reaching their full advance position, than the engine will not reach full power and probably overheat.

[High On Octane]

The above all sound like very viable possibilities.  To me it sounds like your exhaust is plugged and choking out the motor.  When you had your motor rebuilt, did they decoke the motor and exhaust?  How many miles are on the bike itself?

Scottie J

[azcatfan]

I agree with the timing call.  Static timing is really just to get you close to where you need to be.  You have to go for a ride, get it to advance, and listen for ping.  Keep advancing the time little bit by little bit, just until your loaded uphill advance begins to ping.  At that point back off the timing just a bit.

Good luck!  Your ride would be an adventure on any bike, you've placed an adventure within your adventure by taking an RE 

[ace.cafe]

As you get higher in altitude, you need to progressively lean out the carb, and advance the ignition timing to suit. Otherwise the bike will suffer rhese kinds of issues.
The Bullet is a very weak bike to begin with, and you have it loaded up with a passenger and luggage/spares. Add in these factors from alritude such as lower compression and wrong mixture and wrong ignition timing for the conditions, and it is no wonder that it can hardly move.

[chumma7]

It's true you will need to lean out the jetting and could benefit from advanced timing as your elevation increases but I would stay away from doing that right now.
In your post you explain you are attempting to climb up ridiculously steep hills in 3rd and 4th gears at low rpms with a passenger and all your belongings. You are most definitely lugging the motor which will soon kill it.  In those conditions, even with a perfectly tuned bike, you should not attempt to use even 3rd gear up steep hills. Many people have a misconception that low rpms means less stress on a motor uphill but its the opposite- your motor will greatly benefit from higher rpms in 2nd gear (less load on the engine) than low rpms in 3rd.
The higher gear presents more load on the motor, causing it to overheat and detonate. The sound you are hearing is ping/detonation. It produces tremendous amounts of heat as well as being the equivalent of hammering the top of your piston with a sledgehammer.  Hopefully you havent done any serious damage already.
Stick to low rpms at moderate to high rpms and take frequent breaks. Consistently monitor your spark plug. When it starts to miss, lean out the jetting and if need be, swap plugs. Leave the timing alone.

[Mike_D]

I'd like to point out that I had a 350 in India loaded with luggage and my chick.  We made it over all the high Ladakh passes (5,000+ meters) without ever rejetting.  At the time I had no idea what jetting the carb was and never met anyone on a Bullet making that run that rejetted their carb.  That's not to say that properly jetting the carb isn't important, or that it wont loose power at high altitudes or that if I did it again I wouldn't jet the carb to suit the altitude.  But I'm thinking the carb isn't necessarily your problem right now. 

I did, occasionally, have massive power loss when climbing hills in Himachal Pradesh -- the problem: shitty spark plug.  Later, in Ladakh I ran into some serious problems climbing even the smallest of hills, problem: bad points.  Your problem might be incredibly simple.  What kind of plug are you running? So many shit plugs in India, sometime mechanics put in the wrong plug.  What is the plug gap set at?  What is the points gap set at?  My 350 used to ping on hills when the gap was set too small.  Many Indian mechanics will just eye the gap, check it yourself with a feeler gauge (maybe the Swiss garage will have them?).

Lastly, Chumma is right, that sound you are hearing when climbing hills in 3rd is ping.  Back off when you hear it.  Don't lug the engine, climb hills in high rpm, take it slow.  You'll be fine.  Let us know what you figure out.

[nisonov]

Hi,

I experienced somewhat similar problems, when my exhaust valve had burned due to retarded timing.

You can check possible leaks if you can stand on top of the kick starter. Do you feel the compression or not?

If not, Another option could be valve lash settings. Are the pushrods too tight? Are there sound for leaks?

Hope you sort this out and continue living the dream!

BR

Andy

[cyrusb]

"So, the problem started after I rebuilt the engine in Delhi." This speaks volumes. Here is my advice, have the bike shipped home and spend some time mastering it. Regardless of what is wrong now, you need to know more about this machine on a long journey like this for your own safety. This is Zippo Lighter technology, so the training won't take long, even if you have to redo the rebuild. Think about it.

[Bala2014]

Below are answers/comments to some of what you all had to say.  Thanks a million for all the help and advice...hope these additions spur some more thoughts....

Is it possible that a baffle in the silencer has become dislodged and is blocking the exhaust flow?  This could still be possible.  I will inspect when we arrive in civilization tomorrow and begin to open her up and really do some finer adjustments. 

Less likely but another possibility:
As you completely rebuilt the engine is it possible the dots on the cam gears weren't aligned properly?  Dots are lined up ok.

I leave the points cover off and run up the hill, if it's not right I pull off and advance or retard the timing at the points plate until it sounds good, no pinging at low speed and pulls crisply.  One question about this...the sound you hear when timing is overadvanced...the ping...is that the same sound you would hear if the engine was overheated and struggling?  I have yet to run this type of timing adjustment yet but I will tomorrow...I'm just afraid that whatever is causing this low power problem (which is leading to overheating) will make this type of timing adjustment innacurate.  I will still try and will start the procedure on a hill with a "just warm" engine"

What octane rating of petrol are you able to get? If you have a higher compression piston you need higher octane.  They have 92 here.  My piston is stock RE.

Just remove the points cover. No need to interfere with the points or timing, just unscrew the condenser and see if there are any rubbing marks on the back of it. Thanks for the idea...I'll check anything!  However, I gave this a look and it seems fine.

To me it sounds like your exhaust is plugged and choking out the motor.  When you had your motor rebuilt, did they decoke the motor and exhaust?  How many miles are on the bike itself?  I will check that for sure.  What exactly do you mean by decoke the motor and exhaust?  We (carefully) scraped the carbon off the piston head and heads if that what you mean...  The bike now has over 40,000 kilometers on it.  But put a new cylinder kit/piston in 7,000k before and the other rebuild stuff about 2,500 ago (bearings, valves, etc.)

As you get higher in altitude, you need to progressively lean out the carb, and advance the ignition timing to suit. Otherwise the bike will suffer rhese kinds of issues.  I have tried this...also the bike was giving me these power issues since just after the engine rebuild (or after the breakin at least)...in all sorts of conditions, low and high altitude with and without adjustments to carb.

Many people have a misconception that low rpms means less stress on a motor uphill but its the opposite- your motor will greatly benefit from higher rpms in 2nd gear (less load on the engine) than low rpms in 3rd.
The higher gear presents more load on the motor, causing it to overheat and detonate. The sound you are hearing is ping/detonation. It produces tremendous amounts of heat as well as being the equivalent of hammering the top of your piston with a sledgehammer.  Hopefully you havent done any serious damage already.  I did not realize this.  Thanks for the heads up.  Im definitely nervous now that I did some damage...for that reason even if I fix the problem once in this city with proper tools and conditions to test I still plan to pull off the head and inspect the valves and piston to make sure i didnt do any damage.

I did, occasionally, have massive power loss when climbing hills in Himachal Pradesh -- the problem: shitty spark plug.  Later, in Ladakh I ran into some serious problems climbing even the smallest of hills, problem: bad points.  Your problem might be incredibly simple.  What kind of plug are you running? So many shit plugs in India, sometime mechanics put in the wrong plug.  What is the plug gap set at?  What is the points gap set at?  My 350 used to ping on hills when the gap was set too small.  Many Indian mechanics will just eye the gap, check it yourself with a feeler gauge (maybe the Swiss garage will have them?).  Ahh!  So you understand what riding an Enfield is like in India!  I second that mechanics there are often just wrench swinging cowboys.  But only once you have been to India do you see how much these bikes can be tested and stand up to the test, even without precision tuning.  So...thanks for the advice, once in Osh I will defintely test all gaps PROPERLY and replace spark plug and give it a go.  All that being said I HAVE gone through 3 plugs and still problem persisting

I experienced somewhat similar problems, when my exhaust valve had burned due to retarded timing.
You can check possible leaks if you can stand on top of the kick starter. Do you feel the compression or not?
If not, Another option could be valve lash settings. Are the pushrods too tight? Are there sound for leaks?
I will definitely be inspecting valves.  And hopefully this Swiss garage (or some other place in this city) will have the tool to test it properly...more on that in a second...As for Valve Lash settings...im not sure what that is but will pass that onto whoever mechanic I get to help me out in Osh and ask him to check that as well as the pushrods.

Here is my advice, have the bike shipped home and spend some time mastering it. Regardless of what is wrong now, you need to know more about this machine on a long journey like this for your own safety.  Not an option...for lots of reasons, but I think its not bad advice and my father would definitely second you.

So, here are some of my new thoughts and questions...first of all I wanted to ask if the compression idea I had is even valid...if compression was off due to poorly seated rings or valves (or what other causes could there be?)...could that cause this...this loss of power?

I also still feel timing could be the main problem but please keep this in mind...when the problem began in Nepal I had THREE Enfield mechanics (over course of 3 weeks) check the timing to try and solve this.  They all "did their thing" all adjusted timing on the plate AND took off the gears cover and fiddled around there.  (mentioning this just so everyone knows that my amateur hands were not the only ones who tried to fiddle with the timing). The first guys tinkering did nothing to solve the problem.  After the second guy I SWEAR it was fixed.  There was a couple big hills and in my memory she cruised right up them, but then suddenly later that day power died again.  This was over a month ago now no Im not sure if that was my imagination that she actually did perform well for a short time.  But anyways, it leads me to this question...aside from points gap, setting the timing by sliding the plate, the condenser, and having the dots lined up...is there some other mechanism or working part etc. that is part of the whole timing system that could be out of whack or that I should inspect?

Again, thank you thank you thank you for all the help and interest.  I will post updates and maybe some photos if I think there is necessity when I get to it all tomorrow after being in the garage and doing some more tests. 

[Bala2014]

NEW CLUE!!!

We are just 50 k from this city and got our butts kicked by another hill and we got to thinking and remembering the conditions and severity of the problem from its inception back in Nepal and the last week here in Kyrgystan and we are certain that it is a problem that has gotten steadily and progressively worse. I thought this might be important to note and in my amateur eyes makes it less likely to be a simple timing issue....

[High On Octane]

Bala - "Decoking a motor" is the process of removing the carbon build up as you suspected.  But, I have seen a few different reports from various members that the header pipe itself is very prone to carbon build up.  In fact someone within just the last couple of weeks posted about how they had decoked their header pipe and it had drastically increased it's lost performance.  What you are describing with your bike is basically the same thing I see when a car develops a clogged/blocked catalytic converter.  The vehicle will slowly start losing power at roughly 150,000-200,000 miles.  Once it starts to clog, the carbon starts acting like a magnet and collecting all the carbon, make performance and efficiency worse and worse and worse until eventually the vehicle won't even start anymore because it can't breath.  I have a feeling this is what is happening inside of your head pipe at the bends.  With 40,000 km on the clock, if decoking the pipe itself was never performed this very well could be the culprit of your problems.

Scottie J

[Bullet Whisperer]

Unless I have missed it somewhere, there has been no mention of checking the compression at the kickstart - what is it like? Is there much resistance going over compression, or does the kickstart go down [too] easily? If you kick over compression very slowly, can you hear any hissing - from inside either port, or down inside the barrel, as the piston moves up the stroke to TDC compression? If so, you have compression being lost at one, or more than one of these areas. What sort of discharge are you getting from the crankcase breather? an excessive amount of blowing might indicate blowby past the piston and rings.
 B.W.

[Vince]

     You are far past the point of an easy internet advised road side fix. Save yourself expense and heartache by finding a real, experienced mechanic. What ever the cost is now, it will be far less than the repeated repairs and road side strandings you are setting yourself up for.
     You probably have a significant engine issue. Doing a "rebuild" only 3,000 miles after installing a new piston is a sure sign of work that is woefully inadequate by my standards. If it turns out to be a "carbon" issue after only these few miles, the problem will recur soon after decarbonizing.
     When you find your mechanic describe what has transpired and give a list of symptoms. Do NOT diagnose. If you tell the mechanic that you want a part fixed, he may take you at your word. Then you will still have the same problems. Just give him all the info. "Just the facts." But don't tell him what the problem is. Let him do his job.
     

[Bala2014]

Ok, so I think we got the problem solved, but still havent given a proper test run (with our bags up a hill).  First of course we inspected the valve seals with the head off and removed the piston and checked the rings...all good.  We arent sure exactly what it was but could have been any number of the following things or a combination of them:

The oil seal on both valve stems were not put on properly and had moved out of place.  This means a little bit of oil was getting into the combustion chamber each time the valve opened, oil doesnt burn like petrol so it basicallly would dilute the air/petrol mixture and cause loss of compression and power.  Solution: remove valves put new oil seals.  While I was at it I reground the valves and seats but they did not seam to leak before and pretty sure that was not part of the problem, but since I had them out I thought it a good idea. 

The other issue we noticed was with the rockers, the threading on one of the 4 stems that hold the exhaust valve rocker in place had been stripped and it was a bit wobbly, also pretty much all the bolts that hold the rockers down were not very tight at all, this means the the valves might not close completely and can also cause loss of compression.

Like Is aid its hard to say what the exact problem was, just taking the whole head and cyclinder off and putting it back together might have solved something in itself...something we didnt even detect.  Luckily the piston, rings, and barrel looked ok so we didnt do any catastrophic damage while running it in such bad shape.  But she's running smooth now!  Two days from now if all goes well we will be running at 14000 feet!

Thanks again everyone for all the help, very very very much appreciated.  Until next time....

[High On Octane]

Good news!  Carry on and be safe!   

[1 Thump]

Dont tighten them more than 5 ft.lb, the rockers I mean. Thats the limit. Otherwise you will have more stripped threads.

[cyrusb]

The valves will close perfectly with the rockers off.