Royal Enfield 350 Electra 2008: Restoration and Upgrades


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Friends,
This thread is about the restoration of my colleague's 2008 model Electra 5 speed. He is the second owner since 8 months. It was already driven for 13500 kms while he took it over. He is a sedate driver and hadn't abused any of his drives be it his RX100 / Aviator / Manza. After few weeks of driving, he experienced inconsistent idling and starting issues. Cleaning the carb and changing spark plug did not solve the problem.
Consulting a few Bullet doctors we dared to open the engine head and see what's inside. This is where this thread should actually start. We saw a nice good scratch on the piston & cylinder indicating a seizure somewhere in the past, by the previous owner. Apart from the valve replacement & lapping, the rest was a DIY job in his parking. Gathering time after office hours we were finally able to fire the engine after a week of manhandling the engine parts. New filter, oil & gaskets went in.


Time to run-in the engine. He had been out of station and I was delighted to use the bullet for the next 3 months. I had carefully run-in the engine keeping the speed less than 60kmph and even changed oil & filter after 1500 kms. After around 2000 kms I had to return the bike back to him upon his arrival. A couple of weeks later he had taken it for a highway drive along with friends who were on FZ, Avenger & Duke390. In a rush of adrenalin to catch up the Duke, he had revved it hard and kept pace with 390 till the engine suddenly lost power and coughed. So you bulleteers know what had happened. The engine had seized. Though he held the clutch immediately and the engine was still idling it generated a weird noise while accelerating on load. Now he starts worrying about his bull again.

This time the bullet was taken to a proper doctor who worked on bulls since his childhood. As he found the connecting rod play a little excessive he suggested an engine rebuild. Apart from the engine rebuild he got the itch to convert it to classic 350. So, below is the list of upgrades he has in his mind and has purchased some parts for the same.
1) Fuel sender in the tank + Fuel gauge in place of Ammeter
2) Tachometer in place of the ign switch
3) Twinspark in place of de-compressor + Machismo type De-comp if there is a need. His bike has a self start
4) Mudguards & seats of classic 350
5) Illuminated switch console of P-220 + BCU + Indicator cutoff with sensor + wiring
6) Complete painting + chrome + Aluminium buffing
7) BS29 CV carburetor
8) Oval resonator Classic style
To be continued...
 
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Fuel Sender for Bullet 350 / Electra

Attached are some pictures of the making of a mounting provision for a fuel sender in the petrol tank. A Bajaj CT100 tank unit was chosen, because the float arm is straight like in a Thunderbird and its fuel meter is round in shape & separately available (which could be accommodated inside the ammeter case). The square piece is 8mm thick and the holes are at the corners of a 3 cm square.

The second set of pictures are of the engine head which has the decompressor hole blocked with a brass bush and tapped to accommodate a second spark plug, because we thought two sparkplugs would aid in better burning of fuel.

@ Ambylovers - The bike belongs to my colleague and I am doing a technical support. I shall ask him For the Mechanic's estimate. It is more of our brain and mechanic's hardwork for these mods. :)
 

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The chassis frame is back after powder coating, and handed over to the mechanic for building the vehicle. Also seen this the picture are the split seats of classic 350 & the Engine case after buffing.
 

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Man, reading the first post was a painful experience.

Actually, I am very angry. How can you treat a Bullet like a Duke and then expect the piston to not sieze? Sorry to say this but I guess your friend got what he deserved. Ditto the first owner.

Nurse her carefully to life. Replace all parts with OEM ones. Replace the block and dont go for 'sleeving'. For God's sake do away with that 'twin spark in place of decompressor' thingumajig - who gave this idea and what was expected out of it?

Any other thing, do let me know. I will guide you in totality.
 
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How can you treat a Bullet like a Duke and then expect the piston to not sieze? Sorry to say this but I guess your friend got what he deserved. Ditto the first owner.

Nurse her carefully to life. Replace all parts with OEM ones. Replace the block and dont go for 'sleeving'. For God's sake do away with that 'twin spark in place of decompressor' thingumajig - who gave this idea and what was expected out of it?

Any other thing, do let me know. I will guide you in totality.
HI Thanks Sam for posting your views. I was worried that there was no one review the progress and post some fruitful comments.
Yes, it was lesson for life time that he wouldn't rev hard a push rod engine. Of course it will be a new bore only as the bike was already on oversize.
Why twin-spark? It makes engineering sense to have 2 sparkplugs for efficiently burning the fuel in such a big bore engine. Also the piston & the combustion chamber is a simple hemi which has no good provision to induce a good swirl which is important for the combustion process, and no wonder why UCEs have 2 spark plugs. With the self started in place, there was no need for the compressor in the past 1 year of use. Still a thunderbird de-compressor will be installed to ease kick starting.
 
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Why twin-spark? It makes engineering sense to have 2 sparkplugs for efficiently burning the fuel in such a big bore engine. Also the piston & the combustion chamber is a simple hemi which has no good provision to induce a good swirl which is important for the combustion process, and no wonder why UCEs have 2 spark plugs.
Ilango, the CI Enfield block is a 50 year old design. The reason why this engine lasts for so long is that its a big engine that is low on power (18bhp @56xx rpm). I am all in favour of extracting more performance, but I feel more strongly that the inherent nature of this engine is more suited to relaxed cruising and it should be enjoyed in that form only. Though I do not have any data to prove this, still I am 100% sure that two spark plugs would reduce the longevity of this engine due to the resultant excess heat generated.

I have seen the CI chamber and am of the opinion that unless one manages to induce more swirl for the fuel/air mixture, generating a second spark alone (that too at the top of the chamber) may not suffice. Still, if you feel the performance/mileage gains courtesy the second plug are worthwhile, by all means please retain this mechanism. Again, I'd love ro have some data. Are you using the TBTS coil?

All the best for the rebuild. Please keep this thread updated.
 
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Though I do not have any data to prove this, still I am 100% sure that two spark plugs would reduce the longevity of this engine due to the resultant excess heat generated.

I have seen the CI chamber and am of the opinion that unless one manages to induce more swirl for the fuel/air mixture, generating a second spark alone (that too at the top of the chamber) may not suffice. Still, if you feel the performance/mileage gains courtesy the second plug are worthwhile, by all means please retain this mechanism. Again, I'd love ro have some data. Are you using the TBTS coil?

All the best for the rebuild. Please keep this thread updated.
Thanks for your wishes Sam, really in need of good wishes. Going through the spare parts list of TBTS / UCE, I am of the opinion TBTS uses 2 separate coils, 1 for each spark plug. Please correct me if I am wrong. Well & good if TBTS has a dual output coil. My plan was to use a dual output ignition coil like the one used in Tata Nano or Hyundai Santro.
Neither have I got any calculations to guarantee an improvement with the 2nd sparkplug. But curious enough to give it a try. Anyways, the head has only a brass bush press fitted in the de-comp hole. So reverting back to De-comp would not be difficult, but only after comparing the results with a twin-spark :).
 
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Yes. Lets see what gains are made by this setup. Was the motorcycle running this setup before the engine had seized or its being done only now?
No, it was running with single spark plug only. The thought of twin spark was an inspiration from a twinplug enfield & other doodads. He had done one back in 2008. So I don't claim myself to be the inventor of this idea.[;)]
 
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Fuel Meter for Bullet

Here with I am attaching some pictures of adapting a Bajaj Pulsar Fuel meter into bullet's ammeter. The P150 meter dial was cut in the periphery and filed a little to take the size of ammeter dial. The housing it yet to be finished, before which I need to know if painting the dial white would be better because the speedometer has got a white dial.
 

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White would look excellent. I would suggest sticking a white radium sticker instead of painting it. The sticker wallah would also get you the E and F markings aesthetically cut out through the printer in a font of your choice.
 
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White would look excellent. I would suggest sticking a white radium sticker instead of painting it. The sticker wallah would also get you the E and F markings aesthetically cut out through the printer in a font of your choice.
Stickerwala, Good idea Sam. I only would want him to stick without the needle being removed.
 
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I don't think it'd be an overkill provided you get the jetting right. Its all a matter of trial and error really. Where will you source the BS carb from?

And since you are going for the BS, it'd be a good idea to replace the stock air filter with a free flow one. However, if I were you, I'd run in the rebuilt engine first and only then go for all these mods - remember that this engine has already been through two seizures.
 
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