Yamaha TTR125LE Hard Starting Question?


Warden5

Member
Dec 17, 2003
2
0
I recently purchased "two" Yamaha TTR-125LE 2003 models. I have had them since July 2003. Ever since I have purchased them they both are a very hard to start. I will spend upwards of 5-10 minutes just to get them to even pop once, usually killing a freshly charged battery, kick starting from the begining would probably leave you with a bum leg. I had them back to the dealer twice and they have found no problems with the carb or starting circuit. Once the bikes fire and get warm they run, start and ride normally, usually staarting within seconds once warm. This problem appears to happen after they have set for more than 4-5 days. The dealer rec. moving the bikes left and right 45 degrees and shaking them to get fuel into the float bowls, I am pulling and holding the choke out in the start position while cranking. Anyone have any suggestions or experiencing the same problem and can share a fix with me. I have had numerous bikes and ATV's over the years and never had this kind of hard or no starts with two brand new bikes. I feel like the bikes are not getting any fuel, and it takes forever cranking to fill the bowls with fuel, usually killing the battery before the first pop is heard. Are there any type of manual fuel pump bulbs that I could squeeze to get fuel into the carb. Any suggestions would be of great help, I am beginning to lose my patience with this model...Thanks
 

Warden5

Member
Dec 17, 2003
2
0
TTR125LE 4 Stroke Tough to Start

Yamaha TTR125LE Hard Starting Question?
I recently purchased "two" Yamaha TTR-125LE 4 stroke 2003 models. I have had them since July 2003. Ever since I have purchased them they both are a very hard to start. I will spend upwards of 5-10 minutes just to get them to even pop once, usually killing a freshly charged battery, kick starting from the begining would probably leave you with a bum leg. I had them back to the dealer twice and they have found no problems with the carb or starting circuit. Once the bikes fire and get warm they run, start and ride normally, usually staarting within seconds once warm. This problem appears to happen after they have set for more than 4-5 days. The dealer rec. moving the bikes left and right 45 degrees and shaking them to get fuel into the float bowls, I am pulling and holding the choke out in the start position while cranking. Anyone have any suggestions or experiencing the same problem and can share a fix with me. I have had numerous bikes and ATV's over the years and never had this kind of hard or no starts with two brand new bikes. I feel like the bikes are not getting any fuel, and it takes forever cranking to fill the bowls with fuel, usually killing the battery before the first pop is heard. Are there any type of manual fuel pump bulbs that I could squeeze to get fuel into the carb. Any suggestions would be of great help, I am beginning to lose my patience with this model...Thanks
 

High Lord Gomer

Poked with Sticks
Sep 26, 1999
11,790
34
The float bowl fills by gravity, so cranking does nothing to help that.

If you really think they aren't geting enough gas, you could try laying the bike almost all the way over until fuel runs out the overflow tubes on the carb then stand it back up and try starting it.

The only TTR125L that I've messed with was also very cold natured and I believe it could use some richening on the pilot jet to get it to start more easily.

Personally, I would take it to the dealer cold and tell them that if the bikes are OK you would like for them to demonstrate how to start them quickly when cold. Each 4 stroke I've had started more easily once you knew the specific "procedure" for each one. Some start better with a slightly open throttle, some will full throttle, some won't start if you touch the throtte at all!
 

Rich Rohrich

Moderator / BioHazard
LIFETIME SPONSOR
Jul 27, 1999
22,839
16,904
Chicago
Verifying whether it really is getting fuel is the logical place to start. Try pulling the brass screw at the bottom of the float bowl. This is used to check float height, but you can use it to determine if fuel is getting into the float bowl. If the float bowl is full fuel should come rushing out as you back off the screw.

If there is no fuel in the bowl , immediately pop the gas cap off to make sure it isn't a venting issue. If you are getting fuel into the float bowl take a close the carb vent hoses.

These engines tend to come from the factory with low speed jetting that is much too lean. Richening the pilot circuit a bit by turning out the fuel screw (under the front of the carb) a bit can aid starting, but you should verify the basics like fuel in the float bowl and good spark before you start adjusting things.
 

ronwest99

Member
Feb 20, 2002
12
0
99% of the time on the TTR the hard starting is due to a pilot jet that is too lean.

I think my bike has a 12.5 or a 17.5 (I can't remember which off the top of my head).
 

Michelle

Sponsoring Member
Oct 26, 1999
1,245
0
With mine, I turn the choke on, fuel on & hold the button for a bit. It's not a half second, it does take a bit of time & I get concerned I'll drain the battery, but never have. There's no way in hell it'll start (usually) if I forget to turn the gas on (often tried). I've also left the exhaust plug in a couple of times & wondered why it won't start (yeah, I'm dumb).
Then again, I started the bike the other week & wondered why it stalled with the choke on & it hadn't warmed up yet. After trying numerous times, someone yelled at me to ask if I'd turned the gas on (nope). I was amazed it'd started at all. I can't remember if that was the first or second day of the weekend, but think it was the first.

At a guess, it'll take a minute or two to start, definitely not 5-10. The other thing I'm wondering about is your gas, as I know with my KDX the one time I couldn't get the usual gas, it was harder to start than usual.

As the bike's aging, I've found it takes less time to warm up (totally as an aside, not relevant whatsoever). My TTR is sometimes not ridden for about a month at a time, so it's not that I ride it every day. The one thing that has been adjusted is the screw that Rich has mentioned, otherwise it's stock.
 

Matt90GT

Member
May 3, 2002
1,517
1
You need to install a 17.5 pilot in the TTR125s. The stock is just to lean and makes the bikes VERY cold blooded.

After that, the main is anywhere from a stock to 110 for airbox mods and full out 115-120 for pipe on top.

After that, just adjust the fuel screw. That should make them start in 3-5 kicks in the coldest weather and then be able to turn off the choke in about a minute.
 

Jaybird

Apprentice Goon
LIFETIME SPONSOR
Mar 16, 2001
6,452
0
Charlestown, IN
I think that having two bikes with the same problem you may well be seeing a pilot jet issue. However, it is cheap and easy to put a couple of properly gapped plugs in and make sure they are good.
I've wrestled with hard starters before, only to find that I needed a good plug, with proper gap, to cure things.
 

Matt90GT

Member
May 3, 2002
1,517
1
Originally posted by Jaybird
I think that having two bikes with the same problem you may well be seeing a pilot jet issue. However, it is cheap and easy to put a couple of properly gapped plugs in and make sure they are good.
I've wrestled with hard starters before, only to find that I needed a good plug, with proper gap, to cure things.

It is a problem with all of them. Jet the pilot up to a 17.5 and life will be better.
 
C

CaNaDiAn,Eh?

Yeah try changing the jetting on the bikes. I had an XR-100 and a 200 and both of them took forever to start and warm up...by the time I sold them I had a strong leg and lots of patience....lol. I think that thats just how those little 4 stroke playbikes are.
 


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