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**petrolhead_chn** · 07-30-2013, 09:09 AM

Re: Discover 125st mileage problem continues

Originally posted by ShantanuD View Post

Hello,
I own a Discover 125 st since last april. Have completed 2 servicing now but the bike is giving me very low mileage still.
I am getting the mileage of 45-50. It's quite shocking for a bike aimed at mileage segment. Here's the story of servicing.
Before servicing I was getting about 45kmpl. For first service I went to authorized bajaj servicing center. They increased the number of problems. I started getting loud chain sound, cold start problem and worst of all I was getting 35-40kmpl. I went again to get the problem corrected. Still I was getting 45-50. I just waited for another service.
For second service I went to other service center. There I asked them if there was any better engine oil available, so they poured in motul synthetic oil. He said for mileage there is some setting. I really doubt what sort of setting can just correct the mileage?
So after servicing bike was running exceptionally smooth for a couple of days. I was really happy. Then I filled in Rs.500 worth of petrol. Total 6.5L and 3.5 L before reserve. I have gone only 130 and it's half a notch above reserve. Even with 50kmpl I should be going anywhere above 170. But again it looks like I am going to get pathetic mileage of below 50. One more thing is, after 50kph, engine struggles badly. Huge vibrations creep in and I have to really twist the throttle to get it beyond 50. It's like engine is begging not to stretch beyond 50kph. With 5 gears thrown in, it should do at least 60kph comfortably. Also after 50kph absolutely loud sound arises from area where chain rotates from camshaft.
I feel like I am cheated. Performance from this bike is absolutely pathetic. I took good care before first 1000 kilometers. Rarely went beyond 50. Now that I have gone about 2200kms and my journey involves highway I have to ride at 60 to reach in time. But then engine literally cryies at that speed. And this bajaj claimed 13 bhp from this. I really doubt it as it completely lacks low end power and not even decent accelaration. I just dont understand what to do now. Even by different service center the problem cannot be solved.

Hi! I understand how you feel about your bike. But I assure you there is a way out of this and it is very simple. You cannot always rely on service centers or mechanics. There are certain things which can be taken care with patience and effort.

From what you have explained, I realize your bike has been running very rich continuously due which the spark plugs, piston and bore might have built up carbon deposits. Carbon on piston and bore is remote possibility on a new bike. But on spark plugs it could be. This can be confirmed only if you could remove the spark plug and post a picture here or you show it to a local mechanic. The tip of spark plug should be between dark tan to brown (but not black) which indicates an ideal mixture. An ideal mixture can always be achieved with patience and effort.

Regarding the chain noise, put your bike on main stand and check the slackness. It shouldn't be beyond 25mm. I hope it is more than 25mm in your bike and hitting the chain guard also if it exists. Get it tightened and lubricated. The chain noise is gone!!!

Post pictures if you can or keep us posted mate!

**ShantanuD** · 07-30-2013, 01:30 PM

Re: Discover 125st mileage problem continues

Originally posted by petrolhead_chn View Post

Hi! I understand how you feel about your bike. But I assure you there is a way out of this and it is very simple. You cannot always rely on service centers or mechanics. There are certain things which can be taken care with patience and effort.

From what you have explained, I realize your bike has been running very rich continuously due which the spark plugs, piston and bore might have built up carbon deposits. Carbon on piston and bore is remote possibility on a new bike. But on spark plugs it could be. This can be confirmed only if you could remove the spark plug and post a picture here or you show it to a local mechanic. The tip of spark plug should be between dark tan to brown (but not black) which indicates an ideal mixture. An ideal mixture can always be achieved with patience and effort.

Regarding the chain noise, put your bike on main stand and check the slackness. It shouldn't be beyond 25mm. I hope it is more than 25mm in your bike and hitting the chain guard also if it exists. Get it tightened and lubricated. The chain noise is gone!!!

Post pictures if you can or keep us posted mate!

Thanks for helping.
I had tried removing spark plug but wires atop it were too firmly fit, so I got worried and couldn't get it removed.

I will however try again and post the photos as soon as I can.
As per what you say, that my bike may be running rich, I however cannot see any significant power delivery from bike. It just makes a lot of noise and vibrates but acceleration is not great. Pulling power is also low.

**petrolhead_chn** · 07-30-2013, 03:08 PM

Re: Discover 125st mileage problem continues

Originally posted by ShantanuD View Post

Thanks for helping.I had tried removing spark plug but wires atop it were too firmly fit, so I got worried and couldn't get it removed.

I will however try again and post the photos as soon as I can.As per what you say, that my bike may be running rich, I however cannot see any significant power delivery from bike. It just makes a lot of noise and vibrates but acceleration is not great. Pulling power is also low.

No problem at all mate. The plug cap appears to be secured tight on the plug. You can either lift the cap with negligible force or put your fore finger and middle finger below the cap like a V-shape and push it up. Then use the ring spanner to remove the left plug and plug spanner for the right side. Ensure engine is cold else you would damage the threads. Easy there! Now post pictures.Regarding power and all we can fix it with some easy procedures. Just because the mixture is rich the bike may not yield power. There is a loss in combustion if there is no proper spark to ignite it which in turn could be faulty or clogged plugs. Let us start with spark plugs first if you please. Don't worry you are going to discover your discover more.

**ShantanuD** · 07-30-2013, 03:23 PM

Re: Discover 125st mileage problem continues

Originally posted by petrolhead_chn View Post

No problem at all mate. The plug cap is appears to be secured tight on the plug. You can either lift the cap with negligible force or put your fore finger and middle finger below the cap like a V-shape and push it up. Then use the ring spanner to remove the left plug and plug spanner for the right side. Ensure engine is cold else you would damage the threads. Easy there! Now post pictures.Regarding power and all we can fix it with some easy procedures. Just because the mixture is rich the bike may not yield power. There is a loss in combustion if there is no proper spark to ignite it which in turn could be faulty or clogged plugs. Let us start with spark plugs first if you please. Don't worry you are going to discover your discover more.

Thank you,
You fill me with immense hope.
Btw, just a random question. Can we fit digital console of pulsar 135 to this bike? I closely saw the shape and screw placement on both consoles. They are identicle. So I think it might fit on discover. I just desperately need a tachometer

**petrolhead_chn** · 07-30-2013, 04:07 PM

Re: Discover 125st mileage problem continues

Originally posted by ShantanuD View Post

Thank you,
You fill me with immense hope.
Btw, just a random question. Can we fit digital console of pulsar 135 to this bike? I closely saw the shape and screw placement on both consoles. They are identicle. So I think it might fit on discover. I just desperately need a tachometer

If you are so desperate to fix it, you can! It is just that the wiring kit may also need replacement and surprisingly it may seize to work anytime

because of the alterations. And you would regret and go back to stock setup. Do you need this mate? Yeah, an electronic tacho may seem tempting but maintenance and reliability is sure a concern especially when it is altered. FYI, the tacho on my 2004 Pulsar is still working including RPM and side stand indicator while the electronic tacho on my friend's FZ malfunctions; fuel gauge not accurate, led busting and all sorts. If you are specific about RPM meter, it can be installed and I am working on it to have it on my Avenger 200. I will keep you posted.

**DukeDey** · 07-30-2013, 04:20 PM

Re: Discover 125st mileage problem continues

Originally posted by ShantanuD View Post

Also after 50kph absolutely loud sound arises from area where chain rotates from camshaft.
I feel like I am cheated. Performance from this bike is absolutely pathetic.

Relax man! There are no issues which cannot be fixed. You just need to zero in to the exact issue.
I have ridden the disco 125st and 60kmph is easily achievable without much drama in the form of vibes.

During your next trip to the svc ask them to ride your bike and if still they say that the bike is fine contact bajaj. But, before going to svc ride another st125. This can be done by borrowing from a friend who owns one or going to a dealer and asking for a test ride. After this if you feel your bike is very different in terms of performance then there is an issue otherwise you might be expecting too much in terms of performance and smoothness from a 125.

Now, regarding the low mileage issue.
From what you have written it actually seems the bike is running a very rich mixture. (the fuel to air ratio is very high) Get you afr(air fuel ratio) adjusted by getting your carb tuned. Clean the spark plugs and if this was the issue bike should be fine.

Else, it can also be possible that your brakes have some issue which tend to be always partially engaged. This would explain the poor performance and mileage. Try rotating both your front and back wheels while your bike is on center stand, if you feel some resistance, this is the problem.

Never trust the svc fellows, always use the recommended grade of engine oil. I dont know what synthetic oil was poured in(most probably motul 7100) but if its too thick compared to the recommended grade then you would feel the bike acting a little sluggish. The difference in performance should not be huge though as mentioned by you. According to how you have explained, it seems like you are not even getting the performance of a discover 100t.

"Chain rotates from camshaft"?
Are you talking about the timing chain or the drive chain.
If its the former ask the svc guys to check your valve, tappets and valve clearance.
If its the latter then ask them to check the chain set and swing arm alignment.

So many issues in a new bike should not be there in the first place. Do take a test ride of another discover 125st and then do all the above.

If after all this you still find that the bike is not performing like it should and the svc is not helping either, write to bajaj with all the service history and exact problem. Also state that problem has been checked by comparing with another bike.

It would be fine bro. Be patient and try to follow what I have written.

Sent from my GT-I9100

**ShantanuD** · 07-31-2013, 01:14 AM

Re: Discover 125st mileage problem continues

Originally posted by DukeDey View Post

Relax man! There are no issues which cannot be fixed. You just need to zero in to the exact issue.
I have ridden the disco 125st and 60kmph is easily achievable without much drama in the form of vibes.

During your next trip to the svc ask them to ride your bike and if still they say that the bike is fine contact bajaj. But, before going to svc ride another st125. This can be done by borrowing from a friend who owns one or going to a dealer and asking for a test ride. After this if you feel your bike is very different in terms of performance then there is an issue otherwise you might be expecting too much in terms of performance and smoothness from a 125.

Now, regarding the low mileage issue.
From what you have written it actually seems the bike is running a very rich mixture. (the fuel to air ratio is very high) Get you afr(air fuel ratio) adjusted by getting your carb tuned. Clean the spark plugs and if this was the issue bike should be fine.

Else, it can also be possible that your brakes have some issue which tend to be always partially engaged. This would explain the poor performance and mileage. Try rotating both your front and back wheels while your bike is on center stand, if you feel some resistance, this is the problem.

Never trust the svc fellows, always use the recommended grade of engine oil. I dont know what synthetic oil was poured in(most probably motul 7100) but if its too thick compared to the recommended grade then you would feel the bike acting a little sluggish. The difference in performance should not be huge though as mentioned by you. According to how you have explained, it seems like you are not even getting the performance of a discover 100t.

"Chain rotates from camshaft"?
Are you talking about the timing chain or the drive chain.
If its the former ask the svc guys to check your valve, tappets and valve clearance.
If its the latter then ask them to check the chain set and swing arm alignment.

So many issues in a new bike should not be there in the first place. Do take a test ride of another discover 125st and then do all the above.

If after all this you still find that the bike is not performing like it should and the svc is not helping either, write to bajaj with all the service history and exact problem. Also state that problem has been checked by comparing with another bike.

It would be fine bro. Be patient and try to follow what I have written.

Sent from my GT-I9100

Ok, so here we go...
I have got photos and videos of problems with my bike.

1. First, that horrendous sound of chain. Check this video

2. Carburetor and AFR adjustment screw. I don't understand what position is should be in. So please help me

3. I took out spark plugs. Here's how they look.

I cleaned the spark plugs and put them back in properly. Don't know if that will help.
About wheels. Front wheel rotates ok. However, there is a slight scratching sound when I rotate it and after 3-4 rotations it stops suddenly. Rear wheel also looks a bit jammed it rotates with a lot of chain sound

**DukeDey** · 07-31-2013, 01:34 AM

Re: Discover 125st mileage problem continues

Originally posted by ShantanuD View Post

Ok, so here we go...

2. Carburetor and AFR adjustment screw. I don't understand what position is should be in. So please help me

3. I took out spark plugs. Here's how they look.

About wheels. Front wheel rotates ok. However, there is a slight scratching sound when I rotate it and after 3-4 rotations it stops suddenly. Rear wheel also looks a bit jammed it rotates with a lot of chain sound

Buddy, the video is Private.

It cannot be said if the carburettor tuning is fine by looking at the pictures. A good mechanic is required but by looking at your spark plugs I can say that the bike is not running a rich mixture as we were thinking, in fact it looks as if the mixture is a little lean, this is tolerable though and should not affect your performance or mileage much.

You mentioned in the 3rd point that the front wheel stops suddenly and the rear wheel makes some noise. This is it man! the reason your bike is not performing and giving you poor mileage. Either the brake is stuck in case of the front wheel(may be a manufacturing defect with the drum or over tightened brake) or the wheel bearing has gone kaput. The noise from the rear wheel can be again bad wheel bearing or over tightened chain. Get this fixed, your bike should be fine. If you have ridden too much with the said defect then your clutch might have taken some toll but that is something we will keep for later. Report back with what is the outcome.

**ShantanuD** · 07-31-2013, 02:01 AM

Re: Discover 125st mileage problem continues

Originally posted by shahbaz63 View Post

Saw it yesterday at kanjurmarg, was surprise to see Daily Commuting Discover in this look, liked it... Looks like its ready to take on

Waiting for a Ownership Review

Originally posted by DukeDey View Post

Buddy, the video is Private.

It cannot be said if the carburettor tuning is fine by looking at the pictures. A good mechanic is required but by looking at your spark plugs I can say that the bike is not running a rich mixture as we were thinking, in fact it looks as if the mixture is a little lean, this is tolerable though and should not affect your performance or mileage much.

You mentioned in the 3rd point that the front wheel stops suddenly and the rear wheel makes some noise. This is it man! the reason your bike is not performing and giving you poor mileage. Either the brake is stuck in case of the front wheel(may be a manufacturing defect with the drum or over tightened brake) or the wheel bearing has gone kaput. The noise from the rear wheel can be again bad wheel bearing or over tightened chain. Get this fixed, your bike should be fine. If you have ridden too much with the said defect then your clutch might have taken some toll but that is something we will keep for later. Report back with what is the outcome.

Check out the video again. Shared it publicly.

**DukeDey** · 07-31-2013, 02:34 AM

Re: Discover 125st mileage problem continues

Originally posted by ShantanuD View Post

Check out the video again. Shared it publicly.

It seems from the video that something is stopping the rear wheel from spinning freely. Show the issue the exact same way you made the video at the svc and they woukd be able to further point out the exact cause. Only by looking at the video nothing concrete can be said but the sound was definitely pointing to an issue with something hindering the free movement of the wheel. Many things can do this, a faulty chain-sprocket kit, wheel bearing, rear drum brakes etc.
Get it done asap else it might effect other components as well as it is stressing tge engine.

Would again say its not a big issue I guess, relax, take it to the svc and show them these exact same thing and they would deal with it fine. By the looks of it if anything is wrong it should be a warranty repair as your bike is roughly 2500kms old. Your bike woukd be fine.

Ride safe!

Sent from my GT-I9100

**petrolhead_chn** · 07-31-2013, 06:10 AM

Re: Discover 125st mileage problem continues

Replied in bold mate!!!

Originally posted by ShantanuD View Post

Ok, so here we go...
1. First, that horrendous sound of chain. Check this video

Has the chain been cleaned ever? I do not think the sprocket and chain will be faulty on a new bike. Clean, lube and adjust chain for correct slack. This is biggest headache on open chain system.

2. Carburetor and AFR adjustment screw. I don't understand what position is should be in. So please help me

It is not about AFR position mate. It is about correct number of AFR turns your bike would accept. Few bikes are comfortable at 2.25 to 2.75 turns outwards from '0' while few others are comfortable only beyond 4 or even 5 turns outwards from '0'. I can help you tune if you please. But I assume this is a new bike and is still under warranty and free service. The SVC guys would set it a little high on the rich mixture only.

3. I took out spark plugs. Here's how they look.
I cleaned the spark plugs and put them back in properly. Don't know if that will help.

How did you clean it mate? Was it shining again after you cleaned it? Did you check the spark plug gap specifications?

About wheels. Front wheel rotates ok. However, there is a slight scratching sound when I rotate it and after 3-4 rotations it stops suddenly. Rear wheel also looks a bit jammed it rotates with a lot of chain sound

This is common on disc brake mechanism. The pads stick to the disc slightly. The pads adjust release themselves automatically as they wear out. When road dust/muck gets accumulated it might appear that it is sticky along with the scratching sound. Clean the pads and disc plate with sandpaper and it should be fine. I don't think the pads are that tight to bring the bike's performance down. If that is the case it will be very much evident.

**ShantanuD** · 07-31-2013, 12:21 PM

Re: Discover 125st mileage problem continues

Originally posted by petrolhead_chn View Post

Replied in bold mate!!!

But the chain sound isn't coming from rear wheel. It is coming from engine. Left side, where toes of the left foot rest, to be precise. It's coming from inside.

**petrolhead_chn** · 07-31-2013, 12:45 PM

Re: Discover 125st mileage problem continues

Originally posted by ShantanuD View Post

But the chain sound isn't coming from rear wheel. It is coming from engine. Left side, where toes of the left foot rest, to be precise. It's coming from inside.

I had a similar trouble on my Avenger as well. I changed the rear sprocket bearing (view my DIY from signature) and the trouble vanished.

Apart from that the minute mud particles in the chain and incorrect slackness is the main culprit. I suggest you to remove the chain, clean it with kerosene and mild toothbrush, lube it with chain lube spray and the set it to correct slack when you put it back. Before putting it back, clean the front sprocket area and the sprocket cover as well. You will be surprised to see hell a lot of muck there. Even after this if the problem exists then do not experiment further, take it to SVC guys who may check your drive shaft bearing.

According to me internal engine components do not bust so easily on a new bike. It is a remote possibility unless you have ripped and abused the bike.

Mate, try working around these small fixes and wait. Still if t is not resolved then take it to SVC to take benefit of warranty.
Remember "Sometimes the solution to most complex problems are simple."

**DukeDey** · 07-31-2013, 12:50 PM

Re: Discover 125st mileage problem continues

Originally posted by ShantanuD View Post

But the chain sound isn't coming from rear wheel. It is coming from engine. Left side, where toes of the left foot rest, to be precise. It's coming from inside.

Bro, I am telling you before you do more harm to your bike take it to svc. Its probably not a big issue but prolong use in this condition might make it worse. Something is not letting your rear wheel spin freely doesn't mean that the sound should come from the rear wheel. The chain drive that spins the rear wheel is connected to the engine near the left foot rest to a small sprocket. With so much noise coming the bajaj people at the svc can't deny that there is an issue. It would be tough for you to DIY. Take it asap and get it fixed.
It'll start giving you all the mileage and power you want after the issue is dealt with.

Sent from my GT-I9100

**ShantanuD** · 07-31-2013, 03:23 PM

Re: Discover 125st mileage problem continues

Originally posted by DukeDey View Post

Bro, I am telling you before you do more harm to your bike take it to svc. Its probably not a big issue but prolong use in this condition might make it worse. Something is not letting your rear wheel spin freely doesn't mean that the sound should come from the rear wheel. The chain drive that spins the rear wheel is connected to the engine near the left foot rest to a small sprocket. With so much noise coming the bajaj people at the svc can't deny that there is an issue. It would be tough for you to DIY. Take it asap and get it fixed.
It'll start giving you all the mileage and power you want after the issue is dealt with.

Sent from my GT-I9100

Alright, got it. Will not mess with it anymore. I will take it to svc.
Thanks guys, your help has been invaluable to me.
Will keep you all updated.

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