2006 YZ 125 Tips & Tricks??

Arkmx
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Arkmx
Edited Date/Time 3/14/2013 9:52pm
.

Well we went and got Zach a 2006 YZ 125 last weekend. It needs a little TLC, front wheel bearings, jetting or reeds etc., I need to give it a good going over before we ride it.

(I ask these question since I have not been around Yamaha's since the YZ 400F back in 98.)

It has PC suspension mods at this time, stock motor with FMF pipe & silencer.

Anyhow do you guys have any tips or tricks for that year YZ 125?

Anything special I need to look out for?

PC or FMF for the exhaust?

Thanks in advance!

Jim.


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thatdad
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thatdad 1/4/2012 7:18am
1/4/2012 7:18am
tass reed cage, one bigger on the rear sprocket, fmf pipe, keep it fresh and have fun
mxtech1
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mxtech1 1/4/2012 7:30am
1/4/2012 7:30am
+1 rear sprocket, VForce reed block, aftermarket exhaust, fresh top ends, jet it, and run race fuel. You won't be disappointed.
millertime603 1/4/2012 8:00am
1/4/2012 8:00am
I had one for awhile.. Loved the bike.. I put DEP pipe and silencer on it. V Force reeds and an ICAT and the bike was the best bike i've ever owned.. You'll be pleasently surprised if you put an ICAT on it (I think they are called I Boost or something now)
FGR01
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FGR01 1/4/2012 8:35am
1/4/2012 8:35am
Check the clutch. It is common for the inner hub to get notched by the steel plates. When it does, the clutch slips. Luckily a new hub is fairly cheap from Yamaha.

While you're in there checking the clutch, check the shift stopper. The 06 had a defective part. Yamaha fixed it in 07 and now only sells the 07+ part as a retrofit for the 06. It is a very cheap part that only costs a few bucks. If you don't replace it and it fails it can destroy your entire transmission. Really good thread here explaining it:

http://www.thumpertalk.com/forum/showthread.php?t=595439

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mx196
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mx196 1/4/2012 8:35am
1/4/2012 8:35am Edited Date/Time 1/4/2012 8:35am
In terms of perormance pretty much everything above, but id reccomend throwing a hinson clutch basket in there for the long run. Especially since you need to use the clutch a little more on the 125...
Moto Mofo
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Moto Mofo 1/4/2012 8:51am
1/4/2012 8:51am
I was going to contribute, but everything above is spot on. If it has a fair amount of hours, check the shift stopper ASAP. These bikes are great.... I love mine. Everytime I ride it, I can't help but wonder how people have forgotten about 125s.
2Mattheseswide 1/4/2012 8:54am
1/4/2012 8:54am
I had an 05, PC works pipe had no noticeable gains, neither did the vforce3. The shorty silencer definitely helped throttle response. I much proffered the stock gearing apposed the one tooth bigger in the rear, but I also only weighed about 130lb when i had it, it felt like it wouldn't pull at all up top in each gear. I had the problem with the shift stopper and didn't know it was a huge problem on others until now.
yamaha581
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yamaha581 1/4/2012 8:56am
1/4/2012 8:56am
My dad sold my brothers pitbike and bought him a used 06 yz125 to mess around on. The only problem was the first time we took it to the track I did a lap on it and the thing locked up. After that we went over the whole bike and found out it had no fluid i the forks the front sprocket bolt was finger tight and the previous owner tried fixing the motor himself. The only good thing is now the bike is all brand new. My brother got some V force reeds for it and a whole fmf exhast and some new graphics. I havent riden a 125 for years until he got it and it was pretty fun!
Tumblin
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Tumblin 1/4/2012 8:56am
1/4/2012 8:56am
2Mattheseswide wrote:
I had an 05, PC works pipe had no noticeable gains, neither did the vforce3. The shorty silencer definitely helped throttle response. I much proffered the...
I had an 05, PC works pipe had no noticeable gains, neither did the vforce3. The shorty silencer definitely helped throttle response. I much proffered the stock gearing apposed the one tooth bigger in the rear, but I also only weighed about 130lb when i had it, it felt like it wouldn't pull at all up top in each gear. I had the problem with the shift stopper and didn't know it was a huge problem on others until now.
I believe the 06 has the improved shift stopper
FGR01
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FGR01 1/4/2012 9:02am
1/4/2012 9:02am
2Mattheseswide wrote:
I had an 05, PC works pipe had no noticeable gains, neither did the vforce3. The shorty silencer definitely helped throttle response. I much proffered the...
I had an 05, PC works pipe had no noticeable gains, neither did the vforce3. The shorty silencer definitely helped throttle response. I much proffered the stock gearing apposed the one tooth bigger in the rear, but I also only weighed about 130lb when i had it, it felt like it wouldn't pull at all up top in each gear. I had the problem with the shift stopper and didn't know it was a huge problem on others until now.
Tumblin wrote:
I believe the 06 has the improved shift stopper
Negative. Read my post above. 05 and 06 had the bad part. It was fixed in 07. If you have an 05 or 06 you need to put the newer part in.
Charles Bronson 1/4/2012 10:13am
1/4/2012 10:13am
jetting jetting jetting. all the power is in the jetting,
Tumblin
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Tumblin 1/4/2012 10:14am
1/4/2012 10:14am
All this flak about 2 vs 4....I get the marketing bullshit, but seriously most scoots are crazy fun. I have the 450 and a '05 125, it takes a lap or two of adjustment when switching (I'm lucky to ride everyother week), the pea shooter is a riot to pin and go, the 450 is very much like that old school mentality of open class management of performance...for me, obviously pro's still pin and go. The 450 is the most forgiving ride that allows me the ability to run most kids pace at 54 with (a perceived) confidence that I'm not going to cripple myself.
I put my '06 450 in an '08 second generation frame and have only adjusted the valves once. Other than Chain, Sprockets, Tires, Grips, Filters, Oil and Suspension maintenance it's factory original. I do split my time on the 125 both track & trail and mostly prefer it when hitting short woods rides. That's also helped keep some hours off the thumper and help keep me from being a lazy ass on the 450.
Arkmx
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Arkmx 1/4/2012 10:19am
1/4/2012 10:19am
.
Thanks for the Heads Up on the Shift Stopper. I will get one ordered and swap it out just in-case it has not been done.

Appreciate the other tips too!

Any more??

JG.

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Arkmx
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Arkmx 1/4/2012 10:22am
1/4/2012 10:22am
.

I have some older PSI Carbs that I may try too!

I know they did well on our other bikes when I had them on Blake's 125's.

.
TerryB
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TerryB 1/4/2012 10:33am
1/4/2012 10:33am
Only performance mods mine has are the Vforce and PC pipe/silencer.

Stock compression, they run great on non-oxygenated 92 with the stock jetting. If you can't find non-oxy 92, 100 low lead avgas works great too, (and cheap) but you might have to do some minor jetting.

Thanks for the shift-stop tip, FGR, never heard that before.

I love this bike! I only wish Yamaha would upgrade the looks and sell it with the 150 kit.
Charles Bronson 1/4/2012 11:21am
1/4/2012 11:21am
TerryB wrote:
Only performance mods mine has are the Vforce and PC pipe/silencer. Stock compression, they run great on non-oxygenated 92 with the stock jetting. If you can't...
Only performance mods mine has are the Vforce and PC pipe/silencer.

Stock compression, they run great on non-oxygenated 92 with the stock jetting. If you can't find non-oxy 92, 100 low lead avgas works great too, (and cheap) but you might have to do some minor jetting.

Thanks for the shift-stop tip, FGR, never heard that before.

I love this bike! I only wish Yamaha would upgrade the looks and sell it with the 150 kit.
TeamGreen
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TeamGreen 1/4/2012 11:25am
1/4/2012 11:25am
TerryB wrote:
Only performance mods mine has are the Vforce and PC pipe/silencer. Stock compression, they run great on non-oxygenated 92 with the stock jetting. If you can't...
Only performance mods mine has are the Vforce and PC pipe/silencer.

Stock compression, they run great on non-oxygenated 92 with the stock jetting. If you can't find non-oxy 92, 100 low lead avgas works great too, (and cheap) but you might have to do some minor jetting.

Thanks for the shift-stop tip, FGR, never heard that before.

I love this bike! I only wish Yamaha would upgrade the looks and sell it with the 150 kit.
Charles Bronson wrote:
[img]http://twostrokemotocross.com/wp-content/uploads/2010/04/2011-YZ250-1.jpg[/img]
That's the bike that Yamaha owes us for $6300.

Geeeze.

No shame!
Charles Bronson 1/4/2012 11:30am
1/4/2012 11:30am
it's just a plastics kit from the netherlands. same 7 year old frame.

but i am pretty sure that after you had it on there, you could order graphics and pre print background for a yzf450 and make it look like a jgr bike

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Tiki
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Tiki 1/4/2012 11:55am
1/4/2012 11:55am
New piston, rings and drive line. Ride, repeat every 20 hours. Until that is done, the rest is wasted money. Enjoy the new scoot.
424
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424 1/4/2012 5:54pm
1/4/2012 5:54pm
We had one, most fun bike I've ever ridden. Did the stopper. I was told they are bad on breaking clutch rods. Put one in the tool box but never used it. Clutch hub was done in a year but it was cheap. I can't remember the jetting we used, but as I remember it made a huge difference cleaning it up. With an exhaust deal we did that as usual. But then one day riding at a track with an ongoing legal battle, I put on the stock stuff just to make less noise. My son actually liked it better. I rode it too. We later did some testing and ended up racing it with stock motor and exhaust. Sure it sounded better and screamed on top with the bling. But it damn sure pulled corners better stock. I think Yamaha actually has good stuff on the 2 strokes.
mx5471
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mx5471 1/4/2012 7:18pm
1/4/2012 7:18pm
Great bike, but do change the shift stopper. I never had a problem, the difference is the original has a small ball bearing on it, and the new one doesn't. Easy to change and doesn't require splitting the cases. Jet it and gear it for your abilities, but DO NOT get an Athena 144 kit. They are junk, and gave us nothing but problems, a used one has to be even more trouble, that's why it's available. If you want an exhaust go with the pc system with the 302 silencer, it performs much better than the fmf system. Run good gas in it and jet it right and it's good to go. Don't worry about the clutch, just slam the gears without using it. It's only needed in turns. It's a tall bike,depending on your son, shaving the seat may be appropriate. I bored the carb 1mm, and polished it, ported the jug, v force 3 reed, and he won the lites class on that bike. It ripped, and it's a great bike. I'll never get rid of that bike. I'm in the process of rebuilding the motor now,after not riding it for 2 years. It still looks like new, and he can't wait to get on it again.
yzmatt
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yzmatt 1/5/2012 4:28pm
1/5/2012 4:28pm
1. Remove engine
2. Ship to Eric Gorr for a 144
3. Install engine
4. Smile endlessly
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holy smoke 1/8/2012 5:54am
1/8/2012 5:54am
Vforce and pipes are a waste of money on a yz 125 ....stock jetting is really close ..depending on how and where you ride you might want to keep a 420 and 430 main in your tool box. Just keep it fresh 15-20 hours if you race and 30 if you dont.

1 tooth larger on the rear, and send the motor to JMS for porting work if you think you need it.

To be very honest a stock 06 or newer yz 125 very close to perfect stock.
Arkmx
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Arkmx 1/13/2012 10:59am
1/13/2012 10:59am
Thanks everyone for the info!

I will post some photos when we get the new graphics and such on it.

JG.

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bd
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bd 1/16/2012 12:35pm
1/16/2012 12:35pm
I have a 2006 YZ 125 and it barks. I have a PC Pipe with a shory. V Force Reeds. My mod that made is scream.... a vortex ignition. Jet the bike and look out. Love my 125
kxking
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kxking 1/23/2012 4:48am
1/23/2012 4:48am
Good luck with your 06, they are excellent bikes.
I am doing a 2005 YZ125 build right now.... will start a seperate thread with picks soon.
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DrSweden 2/11/2013 3:28pm
2/11/2013 3:28pm
FGR01 wrote:
Check the clutch. It is common for the inner hub to get notched by the steel plates. When it does, the clutch slips. Luckily a new...
Check the clutch. It is common for the inner hub to get notched by the steel plates. When it does, the clutch slips. Luckily a new hub is fairly cheap from Yamaha.

While you're in there checking the clutch, check the shift stopper. The 06 had a defective part. Yamaha fixed it in 07 and now only sells the 07+ part as a retrofit for the 06. It is a very cheap part that only costs a few bucks. If you don't replace it and it fails it can destroy your entire transmission. Really good thread here explaining it:

http://www.thumpertalk.com/forum/showthread.php?t=595439
Tnx for the tip. Ordered a new one and changed mine. I think I was in the clear since there was NOTHING left on my previous stopper as the bearing was totally gone, no balls, no ring just the hub.

I assume previous owner saw pieces in the oil and felt, whatever because I found nothing in tranny? Or those pieces are hidden somewhere? Anyway only took me an hour, and I can now find neutral without any issues which was damn hard previously...

Next issue is that the carb is pissing gas after been standing for 6 mos. I tried to clean it at the track, halted the pissing only to come back the next time I rode. I have the petcock on 3/4 which works when engine is on, but as soon as I stop, it's pissing again. Obviously I need to clean it...
FGR01
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FGR01 2/11/2013 4:28pm
2/11/2013 4:28pm
DrSweden wrote:
Tnx for the tip. Ordered a new one and changed mine. I think I was in the clear since there was NOTHING left on my previous...
Tnx for the tip. Ordered a new one and changed mine. I think I was in the clear since there was NOTHING left on my previous stopper as the bearing was totally gone, no balls, no ring just the hub.

I assume previous owner saw pieces in the oil and felt, whatever because I found nothing in tranny? Or those pieces are hidden somewhere? Anyway only took me an hour, and I can now find neutral without any issues which was damn hard previously...

Next issue is that the carb is pissing gas after been standing for 6 mos. I tried to clean it at the track, halted the pissing only to come back the next time I rode. I have the petcock on 3/4 which works when engine is on, but as soon as I stop, it's pissing again. Obviously I need to clean it...
You need to find out where the pieces of that bearing went. Make damn sure they aren't still in the tranny somewhere. Quite a few guys have had their tranny destroyed by these. Maybe the previous owner cleaned all the pieces out but never realized where they came from. The shift stopper looks kind of normal when just the inner race of the bearing is still there.

As for the carb leaking, Yamaha sells a replacement float needle and seat set. The rubber tip on your float needle probably has a groove worn it in. When that happens it won't seal.
DrSweden
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DrSweden 2/12/2013 3:08pm
2/12/2013 3:08pm
FGR01 wrote:
You need to find out where the pieces of that bearing went. Make damn sure they aren't still in the tranny somewhere. Quite a few guys...
You need to find out where the pieces of that bearing went. Make damn sure they aren't still in the tranny somewhere. Quite a few guys have had their tranny destroyed by these. Maybe the previous owner cleaned all the pieces out but never realized where they came from. The shift stopper looks kind of normal when just the inner race of the bearing is still there.

As for the carb leaking, Yamaha sells a replacement float needle and seat set. The rubber tip on your float needle probably has a groove worn it in. When that happens it won't seal.
Crap, this means one has to split the cases? I'll take my chances, hopes for previous owner did it Pinch

Good suggestion about the needle and seat set. Just asked about this on Thumpertalk, most likely could be the issue. Do you see this with your eyes, or you just change it and do a trial and error thing?
FGR01
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FGR01 2/12/2013 5:51pm
2/12/2013 5:51pm
DrSweden wrote:
Crap, this means one has to split the cases? I'll take my chances, hopes for previous owner did it :pinch: Good suggestion about the needle and...
Crap, this means one has to split the cases? I'll take my chances, hopes for previous owner did it Pinch

Good suggestion about the needle and seat set. Just asked about this on Thumpertalk, most likely could be the issue. Do you see this with your eyes, or you just change it and do a trial and error thing?
I's easy to test the needle and seat.

Take the carb off the bike. Remove the float bowl. Hold the carb next to the bike and attach the fuel hose from the tank. Open the tank petcock. Fuel will run straight through the carb and out the bottom. If you push up lightly on the float it should easily stop the flow of fuel.

The needle has a rubber tip on it and usually it gets a noticeable groove worn in it. Maybe not but it easy enough to replace anyway.

Also, take the float off and put it in a dish of gas. Make sure it continues to float for a few hours. Push it under with your hand and make sure no air bubbles come out. If it has any holes it won't work properly in the carb.

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