Got the top end, broken in... Now the problems...HELP

Ok , got the new piston and rings, replace the gaskets, and clean the power valve and carb, here is the lay down:

 

NOTE : My references are street bikes so i dont know what to expect from a dirt bike...

 

1. Broke-in the new top end. bike started on the second kick ( nice...)

2. theres kind of a grinding noise coming from the rear wheel, dont know if its bearings or chain have to check.

3. This thing would not butch an inch when off and in gear (obviously with the clutch pulled).. my street bike rolls in gear with clutch in, so dont know if a dirt bike is suppose to move or not.

4.Idle screw does nothing. turned in or out the bike just dies when idling.

5.theres a slight bogging when snapping the throttle.

6. TRANNY OIL BOLT IS SEIZED and rounded off, tried impact gun with bolt extractor and nothing.

7. After i broked in the piston, went for a 15 minute ride, got a half an inch with line of sludge down my exhaust (MOTUL 32:1)

 

8.IM SCARED SHITLESS OF THIS BIKE

 

Ok , got the new piston and rings, replace the gaskets, and clean the power valve and carb, here is the lay down:

 

NOTE : My references are street bikes so i dont know what to expect from a dirt bike...

 

1. Broke-in the new top end. bike started on the second kick ( nice...)

2. theres kind of a grinding noise coming from the rear wheel, dont know if its bearings or chain have to check.

3. This thing would not butch an inch when off and in gear (obviously with the clutch pulled).. my street bike rolls in gear with clutch in, so dont know if a dirt bike is suppose to move or not.

4.Idle screw does nothing. turned in or out the bike just dies when idling.

5.theres a slight bogging when snapping the throttle.

6. TRANNY OIL BOLT IS SEIZED and rounded off, tried impact gun with bolt extractor and nothing.

7. After i broked in the piston, went for a 15 minute ride, got a half an inch with line of sludge down my exhaust (MOTUL 32:1)

 

8.IM SCARED SHITLESS OF THIS BIKE

One thing at a time...

2- take the chain off and spin the wheel by hand and see if you can hear the noise.  Might be a wheel bearing or some rust on the brake rotor.

3-your clutch plates could be stuck together.  Might not be a biggy. If I let my softail (HD) sit, the clutch sticks till I shift it once, they get lubed, no biggy

4-take your carb apart, sounds like you have a plugged low speed jet or passage plugged.  Carb cleaner and time and patience

5-see low speed jet plugged

6-this suX!  I had this.  I used some power blaster stuff, gentle tapping to vibrate the part, cross fingers! might have to warm it up a bit.  Don't get crazy with the heat!

7- no biggy, yet, could be jetted fat(rich)  write down what main jet you have, and what clip the needle is on when you have the carb apart.  Check float level too.  Spoog is just running rich.  Take your time breaking in the motor!  several heat cycles, no lugging, vary the rpms.

 

Take it one thing at a time!!  Get the service manual!  Document everything!  Stay with a quality oil.  I am not familiar with the oil you used but I am sure some on here are.

Thaks man, really appreciate you take the time...

Using motul 800 and repsol for the tranny

Also some how my bike,has eurospec jetting. 175 52 third clip...

Thaks man, really appreciate you take the time...

Using motul 800 and repsol for the tranny

Also some how my bike,has eurospec jetting. 175 52 third clip...

 

Motul 800 is a waste running it at that ratio, I run 50:1 using that oil.  That oil is some of the best out there, you dont need to run it that thick!  There is no advaltage. just costs yo more money overall.

 

Before anybody tells me thats wrong, I have 150+ hours on it at 50:1, the piston change at 100 hours looked like I could have waited longer even, and the comp was still high.

And my Powervalve at 100 hours didnt even need any real cleaning, just a little spray of brake clean and its like butter.  never have any spooge, can hardly tell its a 2 stroke by looking at the pipe.

 

And I ride it hard, not just putting around in 1-3rd gear on tight trails, lots of Desert use using 5th gear WOT for long periods of time, it just needs to be jettet properly.

 

tranny bolt, try and heat the case and put an ice cube on the bolt for 10 seconds, should come right off.

 

Like said above, remove chain to isolate the problem and go from there.

 

And you have a clogged pilot jet in your carb (the smallest one, first to clog every time!)

For the time beign im going to drain the oil through the clutch cover, untill i come up with a new solution, im leaning towards welding a bigger nut...

Or dermal two flat edges so a wrench can get on there with bite...use little heat!also don't over torque during install you'll crack you're case

I dont think thats going to work I actually tried the bolt extractor with an impact gun ..and thats never failed me before., but it just ended rounding of the bolt

Welding a nut on will work.  The heat from welding shrinks the old bolt and releaves the tension making it easy to back out.

 

MX bike clutches generally drag when cold.  It will be hard to push in gear with the clutch in but should not be impossible.  If the drag is excessive it is likely a warped plate, notched basket, or a worn release cam.

 

Don't worry much about what everybody says about your oil it does not matter what you do so long as your bike is jetted to do it.

 

The spooge out your pipe is probably from idling it a bunch while you broke it in, repack the pipe.

 

The idle issue, well these things don't idle well but you should be able to get it to idle if its running properly.  This may go along with the bog.  If you let the bike idle for an extended period of time you it will bog when you rev it, you need to get it on the pipe a bit to clear it out.  If it continues to bog you've got a plugged jet or a fouled plug.   A chipped or cracked reed valve will also make a bike bog.

Edited by 1987CR250R

Welding a nut on will work.  The heat from welding shrinks the old bolt and releaves the tension making it easy to back out.

 

MX bike clutches generally drag when cold.  It will be hard to push in gear with the clutch in but should not be impossible.  If the drag is excessive it is likely a warped plate, notched basket, or a worn release cam.

 

Don't worry much about what everybody says about your oil it does not matter what you do so long as your bike is jetted to do it.

 

The spooge out your pipe is probably from idling it a bunch while you broke it in, repack the pipe.

 

The idle issue, well these things don't idle well but you should be able to get it to idle if its running properly.  This may go along with the bog.  If you let the bike idle for an extended period of time you it will bog when you rev it, you need to get it on the pipe a bit to clear it out.  If it continues to bog you've got a plugged jet or a fouled plug.   A chipped or cracked reed valve will also make a bike bog.

Awesome... i believe you are right, after i broke in the engine i wiped of the spooge and went for a ride around neighborhood, i got on the pipe a couple of times and when i got back there was no spooge so im torn on that one..

 

Also i got a skf dealer near my home, and got the bearings for the front and rear, is it safe to get those bearings from them? .or do i need a specific type of bearing. I know i replace my street bikes bearing with them without issues

I use a torque wrench to tighten my oil drain bolt. It's surprising how much I've been over tightening it without one.

Edited by Mrbinkels

I use a torque wrench to tighten my oil drain bolt. It's surprising how much I've been over tightening it without one.

i dont touch a bolt with out one , but po was the one who worked on it.....

Ok cleaned carbs, she idles and can get the idle screw to work now....

I tried the air screw tunnig guide, turning it in then out and finding out if my pilot is rich or lean... turns out is rich im currently using #52 pilot jet, buying a 50 and 48 to see

 

Is the sound im hearing from the pipe like someone is hitting it with a metal object the pinging?

I hear it sometimes but i thought that was normal on a 2t

Edited by thieaux

Awesome... i believe you are right, after i broke in the engine i wiped of the spooge and went for a ride around neighborhood, i got on the pipe a couple of times and when i got back there was no spooge so im torn on that one..

 

Also i got a skf dealer near my home, and got the bearings for the front and rear, is it safe to get those bearings from them? .or do i need a specific type of bearing. I know i replace my street bikes bearing with them without issues

Bearings are bearings, skf are good bearings, use the all the time.  Much cheaper than that stuff you get at the "stealer ships".  I usually write the numbers down or take the old ones in with me.  Sure, replace them all if questions them.  Cheap and be done with it, move on to something else.  Go get 'em.

Ok cleaned carbs, she idles and can get the idle screw to work now....

I tried the air screw tunnig guide, turning it in then out and finding out if my pilot is rich or lean... turns out is rich im currently using #52 pilot jet, buying a 50 and 48 to see

 

Is the sound im hearing from the pipe like someone is hitting it with a metal object the pinging?

I hear it sometimes but i thought that was normal on a 2t

I recommend you start from stock baseline jetting. YZ's re jetted pretty dam close to perfect right out of the box. If anything you usually need to richen jetting to compensate for colder fall temps. I also recommend you do a compression test to verify you have sufficient compression. Even though you have a fresh piston, doesn't guarantee good compression, as you may have a worn out of tolerence cylinder.  What bike do you have ?

I recommend you start from stock baseline jetting. YZ's re jetted pretty dam close to perfect right out of the box. If anything you usually need to richen jetting to compensate for colder fall temps. I also recommend you do a compression test to verify you have sufficient compression. Even though you have a fresh piston, doesn't guarantee good compression, as you may have a worn out of tolerence cylinder.  What bike do you have ?

I was having problems dialing in the carbs, it felt like it was running rich so i moved  the clip up thus lowering the needle (i still dont quite get the terminologies)...and it felt a lot better. Still feels kind of bogging from the bottom....I have a yz250 2004. I checked my settings it seems i have euro specs bike ... 175s pilot 52, power 55 and a n3cw on the 3rd clip

Wooooohoooo, was at my local mx shop, and ran into an old friends brother whos into enduro, and we got talking and since he was an old timer the local pro really looked up to him and he got him to take me next sunday to the local track for a mx101 class.... :banana:  :banana:

More good news.... 

 I finally got the seized rounded off drain bolt, used a mapp torch for 3-5 minutes solely on the bolt , tapped an extractor one size down and used the impact gun...off it came "perfect threads"  yeah, im on my way now....

 

Need some decent graphics anyone care to pitch in..

OK..... Update #2:

 

Its been really hectic at work lately so today i dug in...

 

 

 I changed my main from 175s to 178 and pilot from 52 to 48, the difference was felt right away lots of bottom end, felt great but after 3/4 throttle it would just die and when i mean die its not bogging or anything it just felt sluggish like there is something holding it  back did a couple of laps around "da hood" it felt better but not there yet..... Im beginning to get a feel for a 2 stroke. Took the manual out and printed out the "tuning guide in the first read section" and went to town on the bike, air screw was dialed in but still no top end, tried the chop thing and could not cut cleanly the plug so gave up that idea and went back to the manual so i went the other way and swapped brass to a 172 main...WOWWWWW got the top end i knew was missing i would say im 90 percent of what i think the bike should feel.

 

Now when i ping the bike in 5th it feels like it wants to rev to moon but it needs a little bit more of something i guess this is where the fine tuning comes in.

The rear bearing situation was resolved it wasnt the bearings, it was the PO who ran chain on the bottom of the chain guard instead of through the chain guard....

After that i decided to try and dial in the rear suspension cause i knew thats not how a dirt bike feels on bumbs and stuff, so i took the seat and plastics off, behold the PO had loosen the spring all the way to the top no f***ing wonder this bike felt like a lazy boy, i still dont understand why, the guy is 6'2 and  im only 5'8 anyway i kind of set the suspension, needles to say its a bitch to get on now (thanks genetics) but ill manage ..

 

Went for a ride before dusk and the bike felt amazing, a completely different animal it was snappy, tight and fast i guess the combination of jetting and suspension was the reason it felt odd.

 

Ohhh before i forget, i kept the ratio to 32:1 according to the manual and after jetting the bike , no more oil baby, well not no more oil but its not gushing like texas oil tower anymore, when im on the throttle i can barely see a thin line of smoke and spooge is down about 95% if i had to put a number on it. 

 

Anyways really like to thank the comunity for helping out and new guys a piece of advice :READ READ READ and comprehend what you are reading it'll make your life easier and would get a better response from the forum..

Edited by thieaux

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