2015 YZ250F PROBLEMS!

sgrimmxdad
Profile picture for user sgrimmxdad
Posts
1491
Joined
7/23/2013
Location
Farmville, NC US
Fantasy
1936th
sgrimmxdad 3/27/2017 12:40pm
3/27/2017 12:40pm
When my dealer repaired it the 16 sensor hadn't come in. So we have been running a 15 sensor until this weekend. Had the 16 sensor in the toolbox. Well went to ride this weekend and the bike hesitated to start. Then the 2nd moto it went to acting up. Came back to pits and it stalled right at the trailer and would not start back. Brought home put on stand would not crank.

All we did was open the 16 TPS sensor package and popped it on bike fired right up. My mechanic was shocked. I had not told him this entire story. He thought it was blown up lol I think. He put it on and kicked and it started on the 2nd kick like it supposed to....
shane55555
Profile picture for user shane55555
Posts
1
Joined
3/31/2017
Location
Norfolk, MA US
shane55555 3/31/2017 9:57am
3/31/2017 9:57am
sgrimmxdad wrote:
When my dealer repaired it the 16 sensor hadn't come in. So we have been running a 15 sensor until this weekend. Had the 16 sensor...
When my dealer repaired it the 16 sensor hadn't come in. So we have been running a 15 sensor until this weekend. Had the 16 sensor in the toolbox. Well went to ride this weekend and the bike hesitated to start. Then the 2nd moto it went to acting up. Came back to pits and it stalled right at the trailer and would not start back. Brought home put on stand would not crank.

All we did was open the 16 TPS sensor package and popped it on bike fired right up. My mechanic was shocked. I had not told him this entire story. He thought it was blown up lol I think. He put it on and kicked and it started on the 2nd kick like it supposed to....
Hi I have a 2014 yz250f that has some bogging problems that only affects one area in the rpm range, definitely thinking its a tps problem after reading this. Is the new tps very difficult to install or would it be better to just have the shop do it for more money? Not too great with all the electrical stuff, thanks
motox331
Profile picture for user motox331
Posts
245
Joined
10/2/2015
Location
IL US
motox331 3/31/2017 12:58pm
3/31/2017 12:58pm
sgrimmxdad wrote:
When my dealer repaired it the 16 sensor hadn't come in. So we have been running a 15 sensor until this weekend. Had the 16 sensor...
When my dealer repaired it the 16 sensor hadn't come in. So we have been running a 15 sensor until this weekend. Had the 16 sensor in the toolbox. Well went to ride this weekend and the bike hesitated to start. Then the 2nd moto it went to acting up. Came back to pits and it stalled right at the trailer and would not start back. Brought home put on stand would not crank.

All we did was open the 16 TPS sensor package and popped it on bike fired right up. My mechanic was shocked. I had not told him this entire story. He thought it was blown up lol I think. He put it on and kicked and it started on the 2nd kick like it supposed to....
shane55555 wrote:
Hi I have a 2014 yz250f that has some bogging problems that only affects one area in the rpm range, definitely thinking its a tps problem...
Hi I have a 2014 yz250f that has some bogging problems that only affects one area in the rpm range, definitely thinking its a tps problem after reading this. Is the new tps very difficult to install or would it be better to just have the shop do it for more money? Not too great with all the electrical stuff, thanks
it looks like its two torx screws and one wiring connector. I'm sure you can change it. if you know how to use a multimeter then you can make sure it is set correctly as well. The manual should lay it out how to accomplish both checking it and replacing it.
kik250
Profile picture for user kik250
Posts
1
Joined
7/11/2017
Location
Erie, PA US
kik250 7/11/2017 2:52am
7/11/2017 2:52am
Sgrimmxdad wow... I cannot believe all the crap you went through to find the problem. I found this thread searching to resolve my own problem on a 2014 YZ250E2 I just purchased February 2017 as a leftover. Two weeks ago I had my feet planted on my pegs going through a fast corner and out of left field I get this bog, pop, and then braaap which made my rear tire just spin out and slam me to the ground breaking my ribs. At that point I didn't really think anything of the bog, pop, brappp, I was in pain and it was time to go home. I parked the bike in the garage until I could move again. There was a good amount of water and mud at certain sections that made a big splash.
Anyways I decided to pull out the bike the other day and go take a ride. I go out to the farmers house (he's really not a farmer I just bust his balls) and start my bike and what do you know, everything you and others have described started happening. My bike has only 7.2 hours on it. I went over the bike at the track, tore it apart several times trying to figure out what the heck happened. I do have a motorcycle tech background. I have the two stroke and know part numbers are different between the two bikes but started looking at oem part numbers and noticed that they changed the o ring and a screw to the tps on the two stroke also. I noticed other posts on this thread mentioning o ring changes n stuff. anyways thanks for all the input everyone. BTW Sgrimmxdad did you ever make a YouTube video or anything? It's 5 am here in PA and well I am about to go out and do some multi metering just to make sure so I don't make an ass out of myself with Yamaha. Honestly that TPS on my carb is the only thing I did not check...

The Shop

See All »
sgrimmxdad
Profile picture for user sgrimmxdad
Posts
1491
Joined
7/23/2013
Location
Farmville, NC US
Fantasy
1936th
sgrimmxdad 7/11/2017 3:56am
7/11/2017 3:56am
kik250 wrote:
Sgrimmxdad wow... I cannot believe all the crap you went through to find the problem. I found this thread searching to resolve my own problem on...
Sgrimmxdad wow... I cannot believe all the crap you went through to find the problem. I found this thread searching to resolve my own problem on a 2014 YZ250E2 I just purchased February 2017 as a leftover. Two weeks ago I had my feet planted on my pegs going through a fast corner and out of left field I get this bog, pop, and then braaap which made my rear tire just spin out and slam me to the ground breaking my ribs. At that point I didn't really think anything of the bog, pop, brappp, I was in pain and it was time to go home. I parked the bike in the garage until I could move again. There was a good amount of water and mud at certain sections that made a big splash.
Anyways I decided to pull out the bike the other day and go take a ride. I go out to the farmers house (he's really not a farmer I just bust his balls) and start my bike and what do you know, everything you and others have described started happening. My bike has only 7.2 hours on it. I went over the bike at the track, tore it apart several times trying to figure out what the heck happened. I do have a motorcycle tech background. I have the two stroke and know part numbers are different between the two bikes but started looking at oem part numbers and noticed that they changed the o ring and a screw to the tps on the two stroke also. I noticed other posts on this thread mentioning o ring changes n stuff. anyways thanks for all the input everyone. BTW Sgrimmxdad did you ever make a YouTube video or anything? It's 5 am here in PA and well I am about to go out and do some multi metering just to make sure so I don't make an ass out of myself with Yamaha. Honestly that TPS on my carb is the only thing I did not check...
No I didn't make a video, probably should have. Still have the bike and we are over 150hrs now and since replacing the TPS no problems. I have said it many times and will always say yamaha should have put out a tech bulletin at the minimum and a recall at best IMO.... I still get a few pms from time to time from members that don't post but have had the same problem....
Tryhard
Profile picture for user Tryhard
Posts
405
Joined
6/6/2017
Location
VA US
Tryhard 7/11/2017 6:17am
7/11/2017 6:17am
I bought a brand new 14' it was always hard to start ... and would seriously have a lean popping when WFO dumb ass dealer tried to tell me it was the stock pipe ... causing it to pop because it was " performance" anyways i sold the bike and i will be carrying my ass to brewer cycles in NC , instead of Commonwealth Power sports in virginia
Freemo
Profile picture for user Freemo
Posts
2
Joined
11/11/2017
Location
GB
Freemo 11/11/2017 2:09pm
11/11/2017 2:09pm Edited Date/Time 11/11/2017 11:59pm
Hi guys. I've just picked up a 2014 YZ250F and it's been suffering from the issues in this thread. It would run fine for about 20 minutes then develop a low rpm misfire. If you gave it a good handful of throttle it ran fine, but out of the bends it was becoming a pain.
I bought a Yamaha FI code reader and it had a code for the air temp sensor, so I replaced it but it made no difference. Then I changed the coolant temp and intake air pressure, still no joy.
I proved the fuel pump was giving out the correct 47psi and replaced the spark plug as a matter of course.
As I was clutching at straws I decided to take it for a ride to see if I could replicate the fault conditions, and sure enough after 20 minutes the misfire returned.
Then I got lucky. I took the fuel cap off and the misfire disappeared. I put it back on and the misfire returned. I gave the fuel cap a shake to see if I could hear the ball bearings inside rattling, I couldn't so the fuel pump must have been pulling a vacuum. I shook it harder and the bearings came loose, put the cap back on and it ran fine so I went straight home and ordered a new one.
It arrives Thursday so I'll report back as it could be the best £45 ive spent on it.
motocross_moe27 4/13/2018 7:26pm
4/13/2018 7:26pm
Hey guys I have a used 2014 Yz250f and it’s having the same bogging issues when throttle is applied, I’m going to change the tps sensor and see what happens! Not to mention problem started after I dumped 1k into the suspension (all new parts and valves) shimmed or cut engine valves or something come up to 500, now it’s bogging out and cutting off after 2 laps! And feels like I’m loosing compression (way to easy to kick) after I change oil it feels decent I guess? Man I have a lemon but plan to make lemon aid Because some people can’t afford to have a glass for the lemon aid...
lcgordon711
Profile picture for user lcgordon711
Posts
627
Joined
11/28/2017
Location
Denver, CO US
lcgordon711 4/17/2018 6:41am
4/17/2018 6:41am
Man you guys got me all worried about my bike now a 14 450. Hope mine is ok. Hope you guys figure out your issues.
RC7
Profile picture for user RC7
Posts
3
Joined
5/1/2018
Location
Minford, OH US
RC7 5/1/2018 4:50pm
5/1/2018 4:50pm Edited Date/Time 5/1/2018 4:51pm
sgrimmxdad wrote:
1SL-85885-01-00 is the NEW #
replaces part #
1SL-85885-00-00 is the one that came on the bike!
Did the 1SL85885-01-00 end up being the fix? I seen you later posted replacing with the 2016? I’m having the same issue. Bought a used 2015 250f and ate the bars 20 mins after riding.
sgrimmxdad
Profile picture for user sgrimmxdad
Posts
1491
Joined
7/23/2013
Location
Farmville, NC US
Fantasy
1936th
sgrimmxdad 5/2/2018 5:11am
5/2/2018 5:11am
sgrimmxdad wrote:
1SL-85885-01-00 is the NEW #
replaces part #
1SL-85885-00-00 is the one that came on the bike!
RC7 wrote:
Did the 1SL85885-01-00 end up being the fix? I seen you later posted replacing with the 2016? I’m having the same issue. Bought a used 2015...
Did the 1SL85885-01-00 end up being the fix? I seen you later posted replacing with the 2016? I’m having the same issue. Bought a used 2015 250f and ate the bars 20 mins after riding.
No, we haven't had any problems with our 16 so far. The new part number did fix the 15!!!
RC7
Profile picture for user RC7
Posts
3
Joined
5/1/2018
Location
Minford, OH US
RC7 5/2/2018 6:18am
5/2/2018 6:18am
Thank you sir. I will purchase the 1SL-85885-01-00 sensor right away!
4csHATER
Profile picture for user 4csHATER
Posts
551
Joined
4/11/2017
Location
The sticks, KY US
4csHATER 5/3/2018 10:53pm
5/3/2018 10:53pm
Hate to re-vice this thread but I have a 2014-15 yz250f that I built with 12.5 hours on entire new engine running a crankworks crank and big bore 270cc piston and vortex ecu, I have several parts in stock and will test back to back, but I’m getting a bog and sputter and pop that is completely inconsistent during my moto after 8-10 minutes of riding hard.


I’m a a-class racer that does a-class maintenance, I have a ton of Yamaha parts in stock including s new yz450f throttle body and ecu, stators, iAT sensor, coil, and all kinds of stuff, I also have a new fuel tank in stock, my original plan was to use a 450 harness and throttle body?
RC7
Profile picture for user RC7
Posts
3
Joined
5/1/2018
Location
Minford, OH US
RC7 5/11/2018 11:45pm
5/11/2018 11:45pm
So I put on the new sensor and thought everything was great. 10 minutes later, nothing had changed.... still cutting out...
sgrimmxdad
Profile picture for user sgrimmxdad
Posts
1491
Joined
7/23/2013
Location
Farmville, NC US
Fantasy
1936th
sgrimmxdad 5/12/2018 1:36am
5/12/2018 1:36am
RC7 wrote:
So I put on the new sensor and thought everything was great. 10 minutes later, nothing had changed.... still cutting out...
So sorry to hear that. Have you checked to make sure the spark plug cap is tight, they will come loose. The only other things I can think of, that was suggested to me during my quest, is to go over your wiring harness and inspect each wire and connection. Put die electric grease in all the connectors. I did put a new wiring harness on during the chase but that didn't fix mine either. Finally stators caused some issues these years, I did replace ours but it did nothing to fix the problem, only the new TPS fixed it.

Good luck and please post if you find the problem.
Freemo
Profile picture for user Freemo
Posts
2
Joined
11/11/2017
Location
GB
Freemo 5/19/2018 12:12pm
5/19/2018 12:12pm
Finally got mine sorted. Wish I'd gone straight to the TPS as that's the only thing that fixed it. Changed every other sensor before I tried it.
sgrimmxdad
Profile picture for user sgrimmxdad
Posts
1491
Joined
7/23/2013
Location
Farmville, NC US
Fantasy
1936th
sgrimmxdad 10/20/2018 10:19am
10/20/2018 10:19am
Yes, looks like you got it all. Again though, I don't think the TPS caused a no spark issue. Have you repacked all the connections with die electric grease and tried to start it again?
DuroTools
Profile picture for user DuroTools
Posts
758
Joined
9/9/2015
Location
Middletown, CT US
DuroTools 10/20/2018 7:55pm
10/20/2018 7:55pm Edited Date/Time 10/20/2018 8:00pm
Shit starting writing this before you made your post with the new bike, good luck! never mind

Did you replace everything electrical with new parts or used parts?
When you rebuilt the motor did you also do the head, I know you said entire but just double checking?
I'm having similar electrical woes with a yz450f, when my capacitor failed it would take at least 7 constant kicks before I would get spark and it was in spec Ohm wise which is the odd thing but that fixed the issue when replaced. I have had a bad stator once on a different bike that would just die on you when it got hot. Like you said it would start right away cold but once it warmed up it would just cut out and die then be a bitch to start again unless you let it cool down. No visual damage, swapped it and fixed the issue.

I have my eyes on a 16 and YZ250f in hopes they aren't as finicky electrical wise but I'm still scared since they are basically the same and thinking of finally joining the orange bandwagon as the safe route!

Pit Row

See All »
MotoMo165
Profile picture for user MotoMo165
Posts
1415
Joined
4/3/2014
Location
TX US
MotoMo165 8/4/2019 7:36pm
8/4/2019 7:36pm
RC7 wrote:
So I put on the new sensor and thought everything was great. 10 minutes later, nothing had changed.... still cutting out...
sgrimmxdad wrote:
So sorry to hear that. Have you checked to make sure the spark plug cap is tight, they will come loose. The only other things I...
So sorry to hear that. Have you checked to make sure the spark plug cap is tight, they will come loose. The only other things I can think of, that was suggested to me during my quest, is to go over your wiring harness and inspect each wire and connection. Put die electric grease in all the connectors. I did put a new wiring harness on during the chase but that didn't fix mine either. Finally stators caused some issues these years, I did replace ours but it did nothing to fix the problem, only the new TPS fixed it.

Good luck and please post if you find the problem.
I just bought a 2016yz250f with 1 hour on it (literally) for 4K.... greasing the electrics will prevent these funny sensor issues or are these issues mainly a concern for the 14-15 models? Also, any issues with the 2016s? Thanks guy, sorta nervous as I was told the bike was a 2017, and the hype and pristine ness of the bike had me glance over the year. Not sure if the guy (rich older guy, stupid money) just didn’t know or purposely lied... but I have a 2016 yz250f. Anything I should be aware of? Thanks.
sgrimmxdad
Profile picture for user sgrimmxdad
Posts
1491
Joined
7/23/2013
Location
Farmville, NC US
Fantasy
1936th
sgrimmxdad 8/5/2019 3:30am
8/5/2019 3:30am
The 16 has the new TPS, so you are good there! Our 16 has been a great bike, no unusual problems at all. There were very minor differences between the 16 & 17, mainly the motor mounts.... So a slight handling advantage is all the 17 had as I understand it!
2
DuroTools
Profile picture for user DuroTools
Posts
758
Joined
9/9/2015
Location
Middletown, CT US
DuroTools 8/5/2019 3:57am
8/5/2019 3:57am
RC7 wrote:
So I put on the new sensor and thought everything was great. 10 minutes later, nothing had changed.... still cutting out...
sgrimmxdad wrote:
So sorry to hear that. Have you checked to make sure the spark plug cap is tight, they will come loose. The only other things I...
So sorry to hear that. Have you checked to make sure the spark plug cap is tight, they will come loose. The only other things I can think of, that was suggested to me during my quest, is to go over your wiring harness and inspect each wire and connection. Put die electric grease in all the connectors. I did put a new wiring harness on during the chase but that didn't fix mine either. Finally stators caused some issues these years, I did replace ours but it did nothing to fix the problem, only the new TPS fixed it.

Good luck and please post if you find the problem.
MotoMo165 wrote:
I just bought a 2016yz250f with 1 hour on it (literally) for 4K.... greasing the electrics will prevent these funny sensor issues or are these issues...
I just bought a 2016yz250f with 1 hour on it (literally) for 4K.... greasing the electrics will prevent these funny sensor issues or are these issues mainly a concern for the 14-15 models? Also, any issues with the 2016s? Thanks guy, sorta nervous as I was told the bike was a 2017, and the hype and pristine ness of the bike had me glance over the year. Not sure if the guy (rich older guy, stupid money) just didn’t know or purposely lied... but I have a 2016 yz250f. Anything I should be aware of? Thanks.
I gave up on the electrical problems with my 450 and sold it and just bought a used 15 250fx and the guy had alot of random electrical problems so while it was in the shop he bought a 18 yz250f but last thing they did at the shop to his 15 was dielectric grease all the connections and I was scared buying it but so far it hasn't given me one issue so kind of wish I did that to the 450 before unloading it.

I replaced the kill switch on the 250 from a fall that broke it somehow and it just looked like vaseline in the connection. I believe the grease is supposed to be petroleum based and so thinking Vaseline would be perfect but I have read of some issues with certain brands of dielectric grease so now I'm wondering what brand to use???
MotoMo165
Profile picture for user MotoMo165
Posts
1415
Joined
4/3/2014
Location
TX US
MotoMo165 8/5/2019 4:05am
8/5/2019 4:05am
Thanks for the replie guys. I’ll see about the dielectric grease before taking her out this weekend!
MotoMo165
Profile picture for user MotoMo165
Posts
1415
Joined
4/3/2014
Location
TX US
MotoMo165 8/16/2019 4:28pm
8/16/2019 4:28pm
I didn’t dielectric grease the rectifier/regulator. I have a 2016 yz250f, should I be concerned?
1
sgrimmxdad
Profile picture for user sgrimmxdad
Posts
1491
Joined
7/23/2013
Location
Farmville, NC US
Fantasy
1936th
sgrimmxdad 8/17/2019 3:15am
8/17/2019 3:15am
MotoMo165 wrote:
I didn’t dielectric grease the rectifier/regulator. I have a 2016 yz250f, should I be concerned?
Should be good but the dielectric grease process is something that needs to be done at least once a year I'd say, especially if you use a pressure washer!
DuroTools
Profile picture for user DuroTools
Posts
758
Joined
9/9/2015
Location
Middletown, CT US
DuroTools 8/17/2019 3:56am
8/17/2019 3:56am
MotoMo165 wrote:
I didn’t dielectric grease the rectifier/regulator. I have a 2016 yz250f, should I be concerned?
sgrimmxdad wrote:
Should be good but the dielectric grease process is something that needs to be done at least once a year I'd say, especially if you use...
Should be good but the dielectric grease process is something that needs to be done at least once a year I'd say, especially if you use a pressure washer!
My bike has all connections even the kill switch greased then some are even taped up with electrical tape and I rode through a 100 yd tunnel that had a foot and a half of water and a retaining pond and the bike never cut out this past weekend so I am a believer in dielectric grease. I also use a pressure washer but am super careful not to direct hit the connections by the top of the radiator shrouds plus the area under the battery with all the connections. I also made a homemade protector to shield that area from old bike plastics.
DuroTools
Profile picture for user DuroTools
Posts
758
Joined
9/9/2015
Location
Middletown, CT US
DuroTools 11/4/2019 4:27pm
11/4/2019 4:27pm
MotoMo165 wrote:
I didn’t dielectric grease the rectifier/regulator. I have a 2016 yz250f, should I be concerned?
sgrimmxdad wrote:
Should be good but the dielectric grease process is something that needs to be done at least once a year I'd say, especially if you use...
Should be good but the dielectric grease process is something that needs to be done at least once a year I'd say, especially if you use a pressure washer!
DuroTools wrote:
My bike has all connections even the kill switch greased then some are even taped up with electrical tape and I rode through a 100 yd...
My bike has all connections even the kill switch greased then some are even taped up with electrical tape and I rode through a 100 yd tunnel that had a foot and a half of water and a retaining pond and the bike never cut out this past weekend so I am a believer in dielectric grease. I also use a pressure washer but am super careful not to direct hit the connections by the top of the radiator shrouds plus the area under the battery with all the connections. I also made a homemade protector to shield that area from old bike plastics.
UPDATE: My bike is now having the dreaded issue or one of the issues I should say. Starts fine initially then once I give it any type of serious gas it backfires pops and cuts out losing power. Guess I'll be trying this part but seems like there is a newer part # now. Anyone have a link to an install video that shows how to set the TPI or do you just put it in the same position that the old one was?
1

Post a reply to: 2015 YZ250F PROBLEMS!