rough acceleration at low rpm

[Jeffthechef]

My much loved 2010 S10 which has taken me to some great locations through several countries has recently been experiencing some rare mechanical problems. I was hoping someone else may have had the same thing happen to their bike and could point me in the right direction before I seek professional advise. I have had the bike from new and have about 150,000km. on it. I have done no modification to the mechanical side of the bike.

The bike has recently started to have a very rough acceleration at low rpm (1000-3000) and seems to misfire while accelerating. The bike also seems to have trouble at cruising at this rpm while at lower speeds and seems to have a slight backfire. At higher rpm's and higher speeds it seems to unnoticeable. I have also noticed that recently the fuel consumption seems to be slightly higher then normal.

Any advise would be greatly appreciated.

 

[Dogdaze]

Possible causes, bad fuel (always a big factor if filled at an out of the way location), bad spark (plugs would be my first change then coils) and of course there is the throttle bodies themselves, butterflies not opening or dirt on the contacts......... Remember, fuel, air, spark.

 

[steve68steve]

Not qualified to answer intelligently, but weird performance at low RPM and backfiring - could that be an exhaust leak? Loose bolt on the header, or maybe a hole punched in the pipe somewhere?


I had a DL1000 that had similar issues when the rubber boot(s) that connect the throttle body to the airbox worked loose or leaked.

 

[AVGeek]

Spark was my first thought as well, especially with your mileage. When (if ever) were the plugs last changed?

 

[Don in Lodi]

How about giving a list of things that have been done maintenance wise, and when. ::024::

 

[oprider]

If this started after riding in a heavy rain?

 

[Checkswrecks]

How about giving a list of things that have been done maintenance wise, and when. ::024::

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At least start with new plugs and a throttle body sync. With that many miles you might consider a serious fuel injector cleaning too.

 

[silvergoose]

What has been the service record for the bike? While, fuel and plugs could add to the problem, when was the last valve check?

Start easy and work your way through. Bad fuel and dirty filters has been the root of many problems, maybe the answer will be fast and inexpensive.

Good Luck

 

[2daMax]

My bet is on the coils, if plugs are confirmed to be fine.

I've read many issues similar to your symptoms, and most point to a bad coil. Most of it occurs at areas where there is a lot of rain.

Bad coil that failed at 'early' life is usually due to water getting into the plug wells and residing there, corroding the terminals to where the electrical contact could not have proper good and reliable connection.

I have changed my plugs and have inspected the coil design and I can see clearly how water can pass the orings and get into the plug wells. There are 2 Orings on the coil but there is a notch on each oring that can allow air to flow out during coil insertion but also allows water to get in. Each notch is positioned 180 degrees away from each other.

Some guy in the UK place another oring that sits between the 2 existing ones and he says it works. When I changed my plugs, I had no idea what size diameter is the right oring, so I just place some good Krytox grease on the notch to impede water from getting in.

 

[RIVA]

Disconnect the TPS on left hand side and work manually by hand. This problem showed it's head with the Gen 1 STs. and this was the cure. Usually showed up around 20k mark on some bikes. !0 minute job and worth a go. IMO

 

[Dogdaze]

Disconnect the TPS on left hand side and work manually by hand. This problem showed it's head with the Gen 1 STs. and this was the cure. Usually showed up around 20k mark on some bikes. !0 minute job and worth a go. IMO

Is this something to do with the contact strips?

 

[RIVA]

This is a sealed unit and apparently the contact areas can get grubby under normal use. By disconnecting the linkage and operating manually through the full movement available a number of times, this helps to clean up the contacts. You will feel a slight resistance as you move it. I have done it to my first Super T after it developed very lumpy running at slow speed. (Like a miss) Cleared it up . There was a lot of posts on the cure on this forum a couple of years ago. I tried a search to no avail.
Just found original post.
http://www.yamahasupertenere.com/index.php?topic=12376.0;topicseen

 

[Checkswrecks]

Disconnect the TPS on left hand side and work manually by hand. This problem showed it's head with the Gen 1 STs. and this was the cure. Usually showed up around 20k mark on some bikes. !0 minute job and worth a go. IMO

I'd forgotten this one.
Thanks!

 

[whisperquiet]

This is a sealed unit and apparently the contact areas can get grubby under normal use. By disconnecting the linkage and operating manually through the full movement available a number of times, this helps to clean up the contacts. You will feel a slight resistance as you move it. I have done it to my first Super T after it developed very lumpy running at slow speed. (Like a miss) Cleared it up . There was a lot of posts on the cure on this forum a couple of years ago. I tried a search to no avail.
Just found original post.
http://www.yamahasupertenere.com/index.php?topic=12376.0;topicseen

I was the last poster on that thread........cleared up the throttle response on my previously owned 2013. It is pretty easy to do as described in the thread.

 

[RIVA]

An update would be appreciated as well as being helpful in future.

 

[Jeffthechef]

Sorry about the delay in posting an update but I have realized that the problem is beyond my knowledge and have booked my S10 in for professional help. Unfortunately due to working commitments this will not be for another week, as soon as the issue is resolved in I will post the results.
The items that will be attended to will be plugs, coil, tps, and a fuel injection cleaning.
I have had all servicing including valve clearance done according to the manual wit the exception of plugs. They have been checked but not changed for over 100,000 km.
Thanks for all the information and suggestions, I will post the results in a little over a week.

 

[Jeffthechef]

I took my S10 into my usual mechanic today to see if the issue of rough acceleration at low speed could be fixed. So far with a change of plugs and tps worked on the issue has not been resolved. Tomorrow he will be looking at the valves and hopefully will have a solution to the problem.

 

[Jeffthechef]

My S10 has just gotten back from my mechanic and is back in good working condition. The fault of the rough acceleration was tight inlet valves. The work carried out was change of plugs, adjust valve clearance, clean throttle body, test coils, test TBS, test injectors and change 2 shims on inlet #1.

 

[scott123007]

Glad to see the problem is resolved. Guess you paid for a couple of valve checks that didn't really happen

 

[RIVA]

Glad to see the problem is resolved. Guess you paid for a couple of valve checks that didn't really happen

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