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Old 6th June 2017, 21:14   #1
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Knocking sound in an Enfield 500?

Hello Bullet Gurus - I own a standard 500 and have done just about 3500 kms. In the past one month or so, have been hearing a weird knocking kind of noise - may be like a clutter ( something like tak tak tak) when I try to accelerate. This knocking sound appears when I just open the throttle at any speed. I get this when I try to accelerate at 20 KMPH or even at 50 KMPH. It then fades away and when I shift gear and open the throttle again, I get to hear that.



No luck at the authorised service centre as I was told to just keep riding and in fact I was also told that this is very common in Standard 500. Wasn't convincing and reaching to you all to seek your inputs and guidance.
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Old 6th June 2017, 23:08   #2
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re: Knocking sound in an Enfield 500?

Your motorcycle may be pinging (pinking) while it is accelerating.

This can be caused by using poor quality fuel so, my first suggestion is, ride for a distance of at least 280 km since the last time you filled the fuel tank.

When you refill the tank, go to a filling station known for its quality fuel and buy the best, highest octane fuel they sell. Then ride your motorcycle and see if the problem has been fixed.

Let us know if this helped.
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Old 6th June 2017, 23:21   #3
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@ArizonaJim - thank you for that input. I will try doing this and get back to you with an update. One question - are you asking me to fill the tank and then ride for 280 kms?

To make sure I don't mix up fuel, I have been dedicatedly using BP unless their fuel quality is bad! Should I try with Shell?
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Old 7th June 2017, 06:25   #4
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re: Knocking sound in an Enfield 500?

I was suggestiing that you use most of the old fuel out of your tank before refilling it with the expensive, high octane fuel. That way you can be sure the old fuel is not reducing the amount of the anti-knock additives that are in the high octane fuel.

I think the fuels sold by BP and Shell are comparable.

One thing I do not recommend is buying any of the after-market "High Octane" or "Anti-Knock" additives sold in Auto Parts stores or in magazine ad's.

Many of them do little or nothing to increase the octane of the fuel in the tank and some of them can actually harm the motorcycles fuel system or spark plug.

Last edited by ArizonaJim : 7th June 2017 at 06:26.
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Old 7th June 2017, 09:02   #5
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@ArizonaJim - thank you. Got it! I will finish up all the existing fuel before trying a new one. Can you recommend where I can fuel up or shall I try out Shell?
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Old 7th June 2017, 10:00   #6
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re: Knocking sound in an Enfield 500?

Quote:
Originally Posted by KK RE Lover View Post
@ArizonaJim - thank you. Got it! I will finish up all the existing fuel before trying a new one. Can you recommend where I can fuel up or shall I try out Shell?
Since your motorcycle is a carburetor version, a lean pilot circuit would also cause the knocking as diagnosed by ArizonaJim. From the factory, the pilot circuit is adjusted very lean for maintaining emission levels. In addition to what ArizonaJim has advised, try tuning the pilot circuit of the carburetor after cleaning the air filter.
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Old 7th June 2017, 10:05   #7
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re: Knocking sound in an Enfield 500?

Quote:
Originally Posted by KK RE Lover View Post
Can you recommend where I can fuel up or shall I try out Shell?
If you want to stick with BP, try Nagpals pump on Residency road. Excellent fuel quality, that I found was way better than the shell I usually use in my T-Jet. They also have 97 octane if you want to give it a go.

If the fuel doesn't solve the issue, you may have an advance/retard problem.

Good Luck
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Old 7th June 2017, 13:19   #8
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Quote:
Originally Posted by adrian View Post
Since your motorcycle is a carburetor version, a lean pilot circuit would also cause the knocking as diagnosed by ArizonaJim. From the factory, the pilot circuit is adjusted very lean for maintaining emission levels. In addition to what ArizonaJim has advised, try tuning the pilot circuit of the carburetor after cleaning the air filter.

Thank you adrian. I will try changing the fuel and adjusting the carburettor too. One help - I'm still not a DIY expert so can you tell me how to adjust the carburettor or what should my ask be to a mechanic. Thanks in advance for your help.

Quote:
Originally Posted by keroo1099 View Post
If you want to stick with BP, try Nagpals pump on Residency road. Excellent fuel quality, that I found was way better than the shell I usually use in my T-Jet. They also have 97 octane if you want to give it a go.



If the fuel doesn't solve the issue, you may have an advance/retard problem.



Good Luck

Thanks Keroo. Did some research and landed upon Nagpals. Let me try there before I make a switch to any other brand. By the way, what's an advance/retard problem?

Last edited by Zappo : 7th June 2017 at 13:26. Reason: Please learn to use the multiquote button to respond to all the posts in one go. Back to back posts are not allowed. Posts merged.
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Old 7th June 2017, 13:32   #9
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Re: Knocking sound in an Enfield 500?

Quote:
Originally Posted by keroo1099 View Post
If the fuel doesn't solve the issue, you may have an advance/retard problem.
Quote:
Originally Posted by KK RE Lover View Post
I'm still not a DIY expert so can you tell me how to adjust the carburettor or what should my ask be to a mechanic.
Thanks to keroo1099 to bring up the ignition part. The knock you are facing may be to an incorrect TPS (Throttle position switch) adjustment as well. From my experience, the mechanics at RE ASS are ignorant of how to adjust the TPS properly. I don't know the type of TPS in Standard 500, but if it is like that of Standard 350, then please refer the following thread.

http://www.team-bhp.com/forum/motorb...ark-uce-3.html

Also if you are not a DIY guy, please get the carburetor tuning done by a competent mechanic as carburetor parts are delicate and costly.
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Old 7th June 2017, 15:33   #10
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Re: Knocking sound in an Enfield 500?

Quote:
Originally Posted by adrian View Post
Since your motorcycle is a carburetor version, a lean pilot circuit would also cause the knocking as diagnosed by ArizonaJim. From the factory, the pilot circuit is adjusted very lean for maintaining emission levels. In addition to what ArizonaJim has advised, try tuning the pilot circuit of the carburetor after cleaning the air filter.
Only tuning the pilot circuit might not cure the pinging/ knocking sound. You might as well try to up-jet the carburetor. On the standard RE carburetor which is a CV type, you'll have to turn the fuel-screw (left side of the carburetor) by 3/4ths to 1/2 turn in the anti-clockwise direction after the engines warmed up.
Many have also used the RD350 Mikuni VM 28 series carburetor.
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Old 7th June 2017, 22:56   #11
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Thank you Adrian and Crankpin. Will start with fuel change and go step by step to see what actually stops it.
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Old 8th June 2017, 00:14   #12
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Re: Knocking sound in an Enfield 500?

What you are experiencing is not from fuel or bad plugs. Anyways try different petrol station and check you plugs then report back. Is your carb properly adjusted? I bet you did the running in by the RE manual. I know what it is but just check for the above and if you can then do post a audio or video file while bike is in neutral and open up the throttle in short intervals. Do tell us how you did the running in from new. I am assuming its not the same sound you hear when bike is started cold which is due to the exhaust cam decompression sticking around 750-800 RPM.
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Old 8th June 2017, 09:00   #13
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Quote:
Originally Posted by Randhawa View Post
What you are experiencing is not from fuel or bad plugs. Anyways try different petrol station and check you plugs then report back. Is your carb properly adjusted? I bet you did the running in by the RE manual. I know what it is but just check for the above and if you can then do post a audio or video file while bike is in neutral and open up the throttle in short intervals. Do tell us how you did the running in from new. I am assuming its not the same sound you hear when bike is started cold which is due to the exhaust cam decompression sticking around 750-800 RPM.

Hello Randhawa. No it's not the cold start sound I'm referring to. On running in, I did it the way the manual asked me to. First 500 kms did not cross 50 and made sure at least 400 of it was in open roads / highways. Haven't abused the bike during running in or for that matter even now. I have till date taken the bike to RE ASS only of who I have no hope. Any carb setting done is just by those guys and I'm not a DIY person so I'm just about to start my search On a good bullet mechanic.

Now the strange thing is, this sound is not audible when the bike idles not even a bit. Even if I open the throttle in neutral not much can be heard but I can hear 😊. It's still difficult to understand the noise in neutral. It's pretty pronounced when I shift each gear and open the throttle - comes at the beginning and as the bike gains momentum fades away.

Yesterday I tried very sedate driving and there is a particular position in the throttle where the sound won't come and if I open the throttle further it starts. But this position is very low from the close position so practically not possible to keep driving this way.

Let me know what you think.
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Old 8th June 2017, 10:36   #14
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Re: Knocking sound in an Enfield 500?

I think it's that metallic pinging/ grinding noise that comes from almost every RE bike when given good throttle inputs. See you can improve the fueling but certain engine sounds cannot be eliminated. I would concentrate on the carburetor and get it fixed so that the engine doesn't starve.
There are some ( not so expensive) ECU upgrades as well in the market but I have no experience using them on REs. An improved carburetor along with optimum ignition timing will definitely improve that lean and hesitant acceleration feel of the Bullet.
Also, almost all carburetted motorbikes and scooters are set "Lean" by the manufacturer. To make matters worse, customers demand "more mileage" which makes service guys lean them further to dangerous levels. This effects and considerably reduces engine life and reliability.

Do check your plugs once in a while to figure out where your tuning is going. If the firing end of a spark plug is brown or light gray, the condition can be judged to be good and the carburetor setting is optimal.

Last edited by Crankpin : 8th June 2017 at 10:42.
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Old 8th June 2017, 10:45   #15
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Re: Knocking sound in an Enfield 500?

This image is a good enough reference for you to read your plugs.
Attached Thumbnails
Knocking sound in an Enfield 500?-sparkplugleanrichoptimal640x360.jpg  

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