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Old 10th December 2010, 15:03   #31
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Re: Converting Light Crank to Heavy Crank in Royal Enfield Standard Bullet 350 1996 M

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Originally Posted by adrian View Post
Hi Sankar, did you ever felt that the vibration of your machine has increased after you moded it into a light weight crank?
None that i could feel apart from the usual Bullet vibrations.
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Old 10th December 2010, 16:06   #32
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Re: Converting Light Crank to Heavy Crank in Royal Enfield Standard Bullet 350 1996 M

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Originally Posted by Sankar View Post
None that i could feel apart from the usual Bullet vibrations.
Hey thanks friend, a friend of mine just upgraded to heavy crank and the vibrations in his bike has become lesser than the time he had a light crank. Just wanted to now if the crank weight had any contribution for it.
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Old 29th August 2011, 13:58   #33
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Re: Converting Light Crank to Heavy Crank in Royal Enfield Standard Bullet 350 1996 M

I recently got a 1968 model 350.. but modified to 90's looks. Still having the original heavy crank but not possible to go below 40km/h in top gear.it jerks and shakes when pulling from 40 in top gear.checked all gears,sprokets all are standard type..any clue
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Old 1st September 2011, 18:19   #34
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Re: Converting Light Crank to Heavy Crank in Royal Enfield Standard Bullet 350 1996 M

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Originally Posted by jeeva View Post
I sincerely don't think that replacing or modifying the lighter crankshaft to a heavier one is such a complicated job as it is made out to be.
To accomodate the heavier crank (size), they even go to the extent of machining off the inner walls of the engine casing and go for engine bearings with higher load bearing capabilities.
Truhtfully, I am shocked that any Enfield owner thinks that his roadside, illiterate mechanic is smarter that 500 odd engineers in the RE factory and all those highly qualified experienced mechanics all over the world!!

Please don't mess around with the engine for no good reason. If the engine is being opened , only then try this heavy crank business.

I read some one post that weights are being added the crank!!! Unbelievable.
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Old 2nd September 2011, 23:17   #35
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Re: Converting Light Crank to Heavy Crank in Royal Enfield Standard Bullet 350 1996 M

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Originally Posted by john doe View Post
I read some one post that weights are being added the crank!!! Unbelievable.
What's so unbelievable in it? AFAIK, throughout the 80's and 90's the crank weighed somewhere at 7.2kgs. From the middle 2000's they had cranks from 9-10 kgs, with the same old bearings. The G2 engines had still heavier cranks. Moreover, when RE says "handcrafted", they really do mean it in every sense.

A well balanced crank shaft (with added weights: plates welded on both sides, turned and faced to perfection) with a double side needle roller bearing on the engine casing is what's been done here in the south for ages, if you are not aware.

Last edited by jeeva : 2nd September 2011 at 23:43.
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Old 2nd September 2011, 23:40   #36
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Re: Converting Light Crank to Heavy Crank in Royal Enfield Standard Bullet 350 1996 M

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Originally Posted by jeeva View Post
Moreover, when RE says "handcrafted", they really do mean it in every sense.
Can you throw some more light on that? So, everything including engine assembly is manually done? Do you know if it applies to the new UCE engines as well?

Sorry for so many questions! Also, if everything is being done manually, there would be more room for human error and inconsistency, right?
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Old 3rd September 2011, 12:54   #37
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Re: Converting Light Crank to Heavy Crank in Royal Enfield Standard Bullet 350 1996 M

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Originally Posted by jeeva View Post
What's so unbelievable in it? AFAIK, throughout the 80's and 90's the crank weighed somewhere at 7.2kgs. From the middle 2000's they had cranks from 9-10 kgs, with the same old bearings. The G2 engines had still heavier cranks. Moreover, when RE says "handcrafted", they really do mean it in every sense.

A well balanced crank shaft (with added weights: plates welded on both sides, turned and faced to perfection) with a double side needle roller bearing on the engine casing is what's been done here in the south for ages, if you are not aware.
Its not the crankshaft weight that I have a problem with. The problem I have is with this local modification of something as critical as the crankshaft.

You cannot just add a couple of pieces on the side and make it look equal and think it is the same as a factory made crankshaft which is either machined on CNC machines or forged. Think of this, an engine running at even the basic 2000 RPM will magnify any imbalance in the crank.

Ask your mechanic if he will give a 5 year guarantee on your engine. Doubt it.
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Old 4th September 2011, 19:02   #38
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Re: Converting Light Crank to Heavy Crank in Royal Enfield Standard Bullet 350 1996 M

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Originally Posted by john doe View Post
Ask your mechanic if he will give a year guarantee on your engine. Doubt it.
First thing, its not about your mechanic or my mechanic. Its all in the precision with which the lathe shop folks do their job(balancing). All the mech does is assemble the engine.
About the guarantee part, my 1990 standard 350 came with ~7kg crank from the factory. In 2006, I got the heavy crank mod (9.4kg) + engine and GB overhaul along with a complete paint/plating job. Today the bike has done 48000kms including two trips around the himalayas. She still rides like a dream. Oversize pinion wheel, some cam wheel shims, a set of rocker arms were the only engine related major parts that were changed in the mean time.
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Old 4th September 2011, 19:42   #39
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Re: Converting Light Crank to Heavy Crank in Royal Enfield Standard Bullet 350 1996 M

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Originally Posted by john doe View Post
Its not the crankshaft weight that I have a problem with. The problem I have is with this local modification of something as critical as the crankshaft.

You cannot just add a couple of pieces on the side and make it look equal and think it is the same as a factory made crankshaft which is either machined on CNC machines or forged. Think of this, an engine running at even the basic 2000 RPM will magnify any imbalance in the crank.

Ask your mechanic if he will give a 5 year guarantee on your engine. Doubt it.
Let me ask you John does your royal enfield Dealer give you a 5 year Guarantee on your bike. man in this age you can't guarantee about a person let alone the machines.

Quote:
Originally Posted by jeeva View Post
First thing, its not about your mechanic or my mechanic. Its all in the precision with which the lathe shop folks do their job(balancing). All the mech does is assemble the engine.
About the guarantee part, my 1990 standard 350 came with ~7kg crank from the factory. In 2006, I got the heavy crank mod (9.4kg) + engine and GB overhaul along with a complete paint/plating job. Today the bike has done 48000kms including two trips around the himalayas. She still rides like a dream. Oversize pinion wheel, some cam wheel shims, a set of rocker arms were the only engine related major parts that were changed in the mean time.
As jeeva said that the Weight addition is done by Machine workers not by the mechanic who opens it up. come to delhi some time or go to Punjab or go down south, i am sure i can show you some multiple examples of Bullets mechanics whom i like to call Crafts men rather tan Mechanics. My Mechanic says that if he assembles a bullet it would be "GUNGA" "DEAF" and you know why because you may have seen bullets with the clatter her and clatter there, all that you can hear in his assembles engines is a sweet Thump thats it.
I did my Bullet with a AVL + CI Bottom, AVL Oil Pump and CI barrel ki, and guess what in last 18000 KM i have run it with just 3 services, done 375 KM, in a single go without any breaks or breakdown and many things like that . i am sure its not all that the COMPANY PEOPLE do is correct.
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Old 4th September 2011, 20:46   #40
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Re: Converting Light Crank to Heavy Crank in Royal Enfield Standard Bullet 350 1996 M

Guys, i think the term 'Crank weight increase' is creating fuss. In fact 'bob/balance' weight portions are not reworked but flywheel portion's weight (& so dia) is increased with a ring of metal pressed on & weld locked at outer periphery of both discs. It shifts rpm-vibe thresholds but doesn't make the engine unreliable.
On a light note, one can lug on a light crank with a bit clutch slip but nothing makes the heavy chap move quick & stay fast

edit:
@ Jeeva, 7kg std? you got any idea if this set reappeared in later Electra's?
i have had a '92 stock std which to me felt a better thumper than '08 electra. Ah, someone please help with factory weight figures for all Ci engines, even if not with exact mfr years.

Last edited by Rennjit : 4th September 2011 at 21:03.
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Old 4th September 2011, 21:26   #41
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Re: Converting Light Crank to Heavy Crank in Royal Enfield Standard Bullet 350 1996 M

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Originally Posted by pinneparayam View Post
I recently got a 1968 model 350.. but modified to 90's looks. Still having the original heavy crank but not possible to go below 40km/h in top gear.it jerks and shakes when pulling from 40 in top gear.checked all gears,sprokets all are standard type..any clue
Sounds like the ignition timing is slightly advanced. If you correct it. you can go at lower speeds
Suresh
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Old 11th November 2011, 10:19   #42
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Re: Converting Light Crank to Heavy Crank in Royal Enfield Standard Bullet 350 1996 M

What does it take to make the bullet sound like this? -


Is it the heavy crank or something else or heavy crank and something else?
I want this sound. What do I do?
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Old 12th November 2011, 13:07   #43
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Re: Converting Light Crank to Heavy Crank in Royal Enfield Standard Bullet 350 1996 M

This sound is a result of a short bottle silencer without any barrels in it. In other words, you can see through it.

But please note that by putting this sort of a silencer, you risk ruining your Enfield engine. It's a long post if I have to tell you what exactly happens but over a period of time, this silencer will deteriorate your engine starting with the valves & valve seats.

Ride safe.

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Originally Posted by sen2009 View Post
What does it take to make the bullet sound like this? -
I want this sound. What do I do?
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Old 12th November 2011, 19:40   #44
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Re: Converting Light Crank to Heavy Crank in Royal Enfield Standard Bullet 350 1996 M

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Originally Posted by john doe View Post
I

Ask your mechanic if he will give a 5 year guarantee on your engine. Doubt it.
My bullet which had its crank done ( made heavier in a shed - no CNC) in the year 2000 is still running fine. It could thump around at an indicated 25Kmph in 4th gear without slipping the clutch. I was also running a full-free flow goldie type exhaust and an almost open intake. I have also seen many brand new bullets being stripped in the shed to do the heavy crank mod.

The old 350 engines are build to such large tolerances that slight imbalances wouldn't cause damage. I remember having read an RT by a renowned journo ( Cathcart i think) in which it was indicated that it is the "inertia" of the engine that makes it such a pleasure to thump around at very low speeds! One couldn't get away with such mods on the current generation singles.
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Old 12th November 2011, 22:27   #45
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Re: Converting Light Crank to Heavy Crank in Royal Enfield Standard Bullet 350 1996 M

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Originally Posted by blackfire_9 View Post
This sound is a result of a short bottle silencer without any barrels in it. In other words, you can see through it.

But please note that by putting this sort of a silencer, you risk ruining your Enfield engine. It's a long post if I have to tell you what exactly happens but over a period of time, this silencer will deteriorate your engine starting with the valves & valve seats.

Ride safe.
Will that happen even is I do the other stuff like K-N filter, "upjet my carb" (I am not totally sure of this) and fill only premium petrol?
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