[mathewmerrin]

Hello all I'm from India and own a 2015 GT which I purchased second hand with around 11000 kms. The bike is in stock condition except for the RE sports silencer. The performance on the highway is good.

However the bike seems under powered under 2500 rpm  at crawling speeds as if there is a flat spot. I test drove another GT from the showroom and it doesn't have this problem, very peppy from the get go.

I really enjoy riding my bike but clueless why the bike lacks the low end torque. Does the ECU needs tuning? Have you guys faced the same problem. Will really appreciate your inputs as service centres here are more good at ruining the bikes.Thanks

[Arizoni]

Welcome to the forum.

The only thing I can think of that could cause your low power at low rps's but still have good power at higher speeds is, the throttle position sensor is out of adjustment.

The sensor is located on the inboard side of the throttle body pretty much in line with the throttle shaft (on the opposite side from the place where the throttle cables attach).  It has an electrical connector on it and a screw to lock it in place.

The Service Manual says this sensor should be putting out 0.6±0.2 volts when the throttle is in its idle position.  The voltage increases as the throttle is opened.  At wide open throttle, the output should be 5.0 volts.

If this sensor is producing a reading lower than 0.4 volts at idle speed, the ECU will think the throttle is more closed than it is at slightly higher engine speeds like, when your riding around.  This will essentially "lean out" or reduce the amount of fuel the injector is injecting so there will be a noticeable loss of power.

This link should send you to one of Singhg5's posts about checking the voltage.

https://forum.classicmotorworks.com/index.php/topic,10309.msg119217.html#msg119217

Here is a link to one of Singh5's excellent videos that shows how to test the Throttle Position Sensor.

https://www.youtube.com/watch?v=TiX8oFtYZls

[mathewmerrin]

Thanks Arizoni for such a quick reply...Thanks bro...

[SSdriver]

Arizoni has given a great answer. Hope it fixes the issue for you.

If you are considering getting the PC-V, it will make a big difference on pulling power throughout the RPM range. It will also help setting the TPS.

Welcome and Good Luck....Jimmy

[mathewmerrin]

Thanks....Jimmy I'm more or less contemplating to fit the RaceDynamics Powertronics piggyback ecu which is roughly 280 USD in India. Difficult to source the PC-V locally.

Also the Indian GT doesn't have the O2 sensor whereas the PC-V has a wire for the O2 sensor. Even if I buy the PC-V no idea what I'll do with the O2 wire of the PC.

[Otto_Ing]

PC-V doesn't have a wire for the O2 sensor. It will work on the indian GT's same way as on the european and us versions. It comes with an O2 eliminator which is plugged in the harnes of those GT's equipped with an O2 sensor.

[ace.cafe]

The Sports Silencer is likely a partial cause for the flat spot. Probably too lean at those rpms.
It may be able to be solved at lower cost with a Dobeck Electronic Jet.

There have been reports here of bikes with Sports Silencer having issues with the stock ECU. PC-V with Stage 1 map typically solved it. Dobeck Electronic Jet should also work. Race Dynamic might do it if you can map it.

[mathewmerrin]

Singh5 has clearly shown how to check the TPS voltage, but how do we adjust the voltage if the numbers are a little off.

I came across a YouTube video which shows how to adjust the TPS on a KTM. https://m.youtube.com/watch?v=JWclkhd6weU

Can we use this method for the conti too.Experts please comment,I don't have much technical expertise.
 Little off topic but also wanted to post a pic of my bike

[gashousegorilla]

    I would just check the TPS voltage first and see if it is off with the bike running and at idle. They CAN move a bit from vibration.  If the GT 's Throttle position sensor is the same as the Bullets, and I imagine it is.  There is a Torx headed set screw that holds it in place , in a slotted opening on the TPS.  If it needs adjustment, you would SLIGHTLY loosen that set screw until it's free, and then move and slightly pivot the TPS  forward or back to adjust the voltage.   SLIGHT movements make a big difference here.. so go slow if you need to adjust.  6.5 vs 6.0 on a bullet can make a difference when your not in closed loop.   Slightly higher readings will richen the mixture and slightly lower reading will lean the mixture across the range.  The TPS can be adjusted independently from the throttle plate, which I wouldn't mess with unless you have .

[KD5ITM]

The issue I have with mine which is a little off topic is, when you're sitting at a stoplight and you want to blip the throttle really quick a lot of times the the bike will act like it wants to stall or will stall completely. With mine when you blip the throttle from 0% throttle it wants to try to stall. If you roll on the throttle just enough to raise the RPM about fifty or a hundred, it won't stall. It only wants to try to stall when you try to blip the throttle really quick from 0% throttle. I've heard of other people having the same issue. Just wondering if there's a fix for it. I do have power commander and filter and Hitchcock exhaust installed. I've done more ridding since February then I normally have since buying the GT it seems like this issue is very slowly starting to be more of an issue the past couple of months. Not very often but once in a while it will even stall as I start to roll on the throttle leaving a stoplight. It's just something about when you first try to crack the throttle from 0%, it wants to try to stall. When I'm rolling away from a stoplight it won't try to stall, just once in a very great while it will stall but it doesn't act like it wants to stall each time. It's only when I try to blip the throttle is when it wants to try to stall. Maybe I could take a video of it.

[gashousegorilla]

  IMHO.... to me it sounds like your rich in the low rpm's and throttle positions, or the bike is not yet warmed up or both.   Same with a flat spot under 2500 RPM's...

[SSdriver]

KD...
I assume you are running the standard stage one map on your PC-V.
GHG is correct about fuel mix causing this type issue.
Try tweaking the fuel at the 0-5% throttle opening. Maybe 5% fuel at a time, and see how it responds. If it doesn't help, just reset the Map back where it was.
...Jimmy

[KD5ITM]

I think when I'm stalled the map I added a little bit of fuel from idle RPM to about 1500 RPMs. Don't remember how much I added but it wasn't much at all. The stock Matt I believe had the setting at 0. The reason why I added a little bit of fuel was for the same problem occurring before the map was installed. And to be honest with you it happens more when the bike is well warmed up and driven several miles then it does when it's idling warming up just after starting it. How to make any difference I always let the bike warm up about 5 to 7 maybe 10 minutes max, before taking off on it.

[gashousegorilla]

   Has it been any better or worse since you added fuel in the idle area's  ... or about the same ?
 Does it ever just putter out and die on you when you come to a stop without blipping the throttle ?

[gashousegorilla]

Hello all I'm from India and own a 2015 GT which I purchased second hand with around 11000 kms. The bike is in stock condition except for the RE sports silencer. The performance on the highway is good.

However the bike seems under powered under 2500 rpm  at crawling speeds as if there is a flat spot. I test drove another GT from the showroom and it doesn't have this problem, very peppy from the get go.

I really enjoy riding my bike but clueless why the bike lacks the low end torque. Does the ECU needs tuning? Have you guys faced the same problem. Will really appreciate your inputs as service centres here are more good at ruining the bikes.Thanks

  Kind of a LOW rpm to be riding these bikes at ... No ?   Especially in a higher gear .  That's lugging the bike.    Do you really spend any length of time UNDER 2500 RPM's ? Are you sure it's a flat spot ?  Or does it feel like  low power down there ? 

[mathewmerrin]

GHG..my concern is that whenever I power the bike from a standstill in first gear the bike kinda pulls but feels somewhat powerless, although at high speeds the power is ok.

I test drove two new bikes kept at the showroom with the same riding style, both felt much more responsive at low rpms.

I guess as ace pointed out,maybe the sports silencer is making the mixture lean..anyways next month ill fit the Powertronic to see if that  helps.

[gashousegorilla]

 Oh !  Ok, I got ya.  Sorry, It's when you accelerate .  Was it like that when you had the stock Silencer on there ?

[mathewmerrin]

Previous owner had actually cut the original exhaust and welded a cheap locally made exhaust. It was not only too loud for my liking but was also leaking exhaust gases as the welds were poorly done.

As soon as I got hold of the bike I bought a new bend pipe and sports silencer. Hence I'm unable to comment the performance would have been with the stock exhaust setup.

Except this issue the bike is flawless, engine is smooth, is good on the highway, surely a headturner when it comes to looks 

[KD5ITM]

   Has it been any better or worse since you added fuel in the idle area's  ... or about the same ?
 Does it ever just putter out and die on you when you come to a stop without blipping the throttle ?

The reason I added a little bit of fuel at the idol RPM and then the next RPM setting up from idle on the map was to help prevent it stalling when you blip it. To be honest with you it never really changed much but I've noticed that it's happening just a bit more the last three or so months. Since breaking in the motor it hasn't installed when idling. I guess another way to explain it, if I'm sitting at a red light after the bike has had plenty of miles to warm up then let's say a Harley stops next to me and he blips his throttle so in return I'll go to blimp my throttle and sometimes it will want to stumble like it's getting ready to stall. Once in awhile but not as often it will completely stall. I notice if I just barely cracked the throttle and then blip it most of the time it will blip just fine and not want to stumble. But if I go from 0% throttle and try to do it that's when it wants to stumble and possibly stall. Sometimes I'll try to blip it three or four times before it will actually blip and briefly rev the engine. Other times it will blip just fine without stumbling or trying to stall. (I tried to take a video the other day when the bike was warming up in the garage and of course, it work just fine and wouldn't try to stumble. So I wonder if the engine needs to be at operating temperature for this issue to start to occur.) I've had this problem ever since the bike was new. Maybe I should just stop showing off and not blip the throttle :-)

[Paul_42]

Mate, mine still does that ,mainly when downshifting in a hurry, I'll grab some throttle and it's like bike is off, nothing at all. Still does this after fitting stage one kit and bypassing o2 sensor. I just live with it as I'm getting used to its quirks.

[L4V]

I have about 300 miles on my '14 and it did this prior to a PC as well as after.  I also have the complete ACE air filter kit.
It's OK if I gently advance the throttle at a stop...doesn't then crap out.
I'm thinking about getting mine dyno tuned...I'm sure that will resolve all issues.  I hope, anyway.
Good luck, all.

[Richard230]

I have about 300 miles on my '14 and it did this prior to a PC as well as after.  I also have the complete ACE air filter kit.
It's OK if I gently advance the throttle at a stop...doesn't then crap out.
I'm thinking about getting mine dyno tuned...I'm sure that will resolve all issues.  I hope, anyway.
Good luck, all.

That does sound like an overly-lean condition to me. Possibly the result of trying to meet the latest Euro 3/4 emission regulations - without updating the old RE fuel injection system (which probably has limited brain power).  I note that my stock 2011 B5 doesn't have that issue and pulls fine from all throttle openings.   

[mathewmerrin]

I was very busy with work, house shifting, etc. Went through SinghG5's post carefully about TPS settings.

Took the TPS readings today, they were 0.66 at throttle closed position and 3.78 volts at throttle fully open position.

Operating voltage was at 5.01 volts, guys are these readings normal. I don't want to fiddle with the factory settings unless it's really required.

[gashousegorilla]

     That would be within spec for a Bullet. .... I would leave it right there .  I can't see or think of why a GT would have a different voltage spec for that TPS.   

  How about trying a compression test ?

[Good Vibes]

Hi Matthew

My GT has a sports muffler and I found that a little increase in back pressure made a big improvement to the bikes running.  Try stuffing some chicken wire into the tail end of the muffler. Roll a small piece of chicken mesh (about a 15mm dia hex holes) into a cylinder and wind it around the inside of outer end muffler wall with a little section of the mesh cylinder pushed down the visible tail pipe on the left side.  You may need to experiment a bit but it is an easy way to see if that could help.

Cheers
Good Vibes

[mathewmerrin]

Hi GHG and Good Vibes,

Since I changed my clutch cable and engine oil the bikes performance has improved a lot..maybe its my mind. Or maybe I'm riding continuously on the highways at higher rpms, anyways the bike pulls like anything.

I recently fitted the double seat and the pillion sitting behind was almost thrown of the seat.

The Gt is one mysterious bike and I love every minute I ride the bike. It sure has its share of tantrums like the erratic speedometer, self start, etc.