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Discussion Starter · #1 · (Edited)
Hi all,

I am a new member to this forum and a owner of a 2006 R6.

I have searched for similar starting problems on other threads and i have seen various answers that i did not comprehend.

I decided to create a new thread in the hope to get a more specific and summarized answers to my problem.

Symptoms
  • Bike will not always start without the use of a little throttle, especially after it has been parked for a while.
  • The idle revs are not steady they fluctuate +-200 revs.
  • Once the bike starts it will not raise the idle to above 1500 as it usual did until it warmed up.

Action taken
Took the bike to many mechanics over a period of 6 month that the problem exists. Each mechanic fixed the issue partially but not complete and the symptoms keep reappearing.
Last service another mechanic took a closer look and attempted to fix the issue. Below is a list of what we did.
  • We change the air filter element.
  • Checked the air pressure sensor and it was within specification (3.15~4.15).
  • Checked the TSP and all was well.
  • Checked and adjusted the EXUP system.
  • Emptied and cleaned the gas tank.
  • Changed some air hosing that was worn.
  • Synchronized the throttle bodies.
  • Changed the battery.

Results
  • The idle became steady by the changing of the air hoses.
  • The bike was able to start without the use of the throttle.
  • The automatic choke that raises the revs when the bike is cold did not fix.

I took the bike and today (after one week from the mechanic) the bike did not start properly. I managed to start it with a bit of throttle and took it again to the mechanic (he has the bike now and told me he will look at it).

I am really disappointed with this problem as I have wasted quiet a bit of money on different mechanics and still we haven't manage to fix the issue.

Could anyone help me and give me different ideas as to what might be the problem. Places and components to check or some other approach to the problem so that i can pass it on to my mechanic and see if we can find a solution.

Thanks in advance :)
 

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Does the idle still bounce around? If the bike isn't starting without the use of throttle, you may have an incorrect fuel/air mixture. Is your bike modded in any way?
 

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Discussion Starter · #4 ·
Does the idle still bounce around? If the bike isn't starting without the use of throttle, you may have an incorrect fuel/air mixture. Is your bike modded in any way?
No the idle is now steady, it was fixed when we replaced some air hoses (i do not know the exact name).
The problems that remain are: Unable to start properly and does not auto choke.
 

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Discussion Starter · #5 ·
You need a valve adjustment.
Thank you, that is something I have not heard before, great, I will pass it on to my mechanic.
By the way is this a simple check or difficult and expensive procedure (just so that i will be prepared, money wise)
 

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I was also going to suggest the valve adjustment. The valve check can take a few hours if you haven't done one before and longer if you get stuck at certain places.

Basically, the throttle bodies have to come off, valve cover comes off, engine cover comes off, then you do the valve check. If the valves are out of spec, you have to take more parts off the bike like the CCT, cams, etc, which can take a lot more time. I don't know what the shops usually charge here since I did my own valve check. I would think a competent mechanic who works on bikes can do it in under 6 hours.
 

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Discussion Starter · #7 ·
Thanks 'Revelations',
I told my mechanic today about the valve adjustment and he agreed that it is a main factor and that it could be causing many stability problems.

He said that if it ends up being the valve clearance that it would take him a full working day and that it is not cheap (he did not specify exactly how much).

He then told me that he things it is unlikely that my bike needs an adjustment due to the fact that usually the valve clearance does not need a lot of maintenance as it is something that does not go out of specification very easy, he said that it should be checked at around 45,000 km and by bike has only done 40,000 plus the fact that I had the issue for a while now (6 months) and that makes it strange.

He then informed me that he will try to see if the cause is something simpler before he proceeds to the valve clearance. He has a hunch that the water temperature sensor might be faulty, he will also try a spare map sensor that he had from another R6 in his shop and then he will do a valve timing adjustment, if these don't work then he will go forth and check the valve clearance.

I did not object to his comments i just told him to do the best he can and to inform me in every step especially if it ends up being the valve clearance so that we can talk more about the cost.

The truth is that i did not understood fully what he meant by the 'water temperature sensor', 'map sensor' and I did not understood the difference between valve clearance and valve timing (it was a full workshop day with customers and I did not want to ask him too many details).

As I am no mechanical expert, do all these sound right to you guys?
 

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It sounds like he has a few good ideas. I checked my valves at 26,000 miles and they were all in spec. It can't hurt to let him try the sensors since it is easier to check. Also, checking the valve clearance shouldn't take too long, but if it needs adjustment, that can take a lot longer.
 

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Discussion Starter · #9 ·
A general update after i took the bike from my mechanic last week.

He told me that he checked all the sensors and that they were within specification.

He told me that the problem was the throttle body synchronization.

I asked him why he didn't see this problem before and he told me that he synchronized the throttle bodies before but his vacuum synchronization tool was faulty (I am not entirely convince by this excuse but never mind).

I guess the result is what counts and that is that after the throttle body was synchronization again the bike starts quite good without the use of the gas and the bike actual chokes automatically (finally).

While cold the rpm rise to about 1800 and when the temperature shows around 48c the rpm drop to about 1200.

The good thing is that my bike did not need a valve adjustment and that the mechanic did not charge me for the final throttle body synchronization as he said that it was his fault and not mine.

Since i am no bike expert and I only have the mechanics word for it, I have some dough but so far so good. I hope that it keeps working well without any further issues and that the mechanic told me the truth.

Again thank you all very much!!! :)
 

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just FYI, checking valves is quite easy. It simply requires removing the air box and moving some hoses/wires out of the way to remove the bolts holding the valve cover. Then remove the timing cover access plug so you can turn the motor over to get each set of cam lobes level with the head surface.. slide feeler gauge in and check the measurement. Turn the motor over with your wratchet for each set of cam lobes.. Easy!

ADJUSTING valve clearances.. that is where the real job takes place. gotta remove the cam caps, sprockets, do the math to calculate new shim sizes, then put it all back together while getting cam sprocket alignment correct so you don't bend valves. But checking em ? easy.

the thing about syncing throttle bodies that most have issues with, is the vacuum hoses of most gauges are too big for the small tubes on the back of the throttle body. So you don't get an accurate reading.. when i do em, i use a piece of safety wire to close down the hose a bit so it slides on tight.
 
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