Two Stroke Motocross
Two Stroke Motocross Forum => Technical => Topic started by: Stusmoke on September 05, 2012, 11:23:09 AM
-
Ok my cr125 isnt starting again. When it was running the mainjet was definitely too rich it had a huge bog when I left it wide open at midrange and below rpm. I think the pilot might also be a little rich. Anyways the original problem i was having once I got it running was oil fouling. This was after it was broken in aswell. It wouldbliterally oil foul it a couple of seconds. So i leaned out the fuel air mixture and had to keep pulling the plug out and cleaning it it between foulings or it was just too smothered to spark. That spark plug was brand new and its still sparking but even though its not oil fouling anymore its no longer starting. The heat range is standard to the bike aswell. Any help would be greatly appreciated. Oh and float height is 15 mil. Sorry for the big fatessage my phone is glitching out on me.
Thanks guys
-
Crank bearings and seals o.k.? No trans. oil being sucked into the crankcase?
-
That theory gets my vote as well.
Crank bearings and seals o.k.? No trans. oil being sucked into the crankcase?
-
x2, when my crank seals went I fouled plugs every five minuets and then the engine would only run for 5 minuets. Go into right side crank and look at the seal, sometimes they slip out and they can be easily put back in, and sometimes they wear out and need to be replaced completely.
-
Mikuni?
-
As stated above check your crank seals.
Also if you have fouled the plug throw it away.
Once a plug is fouled it will always be fouled regardless of how you clean it.
-
Here is a thread on thumpertalk (go figure) on pressure testing a 2 stroke:
http://www.thumpertalk.com/topic/432226-pressure-testing-a-2-stroke/
-
As stated above check your crank seals.
Also if you have fouled the plug throw it away.
Once a plug is fouled it will always be fouled regardless of how you clean it.
I was planning on it, I was only using this one cos I didn't have a spare.
Anyway after extensive thinking I've resolved to take it to the local shop cos I won't get a chance to take a serious poke at it for about a month and have it fixed there, shouldn't be too expensive. Once thats done I'll sell both of them and buy a brand new 2013 150 sx if I can. It depends on what finance is available to me at the time. Also needs a new water pump seal theres coolant getting into the tranny oil. Hell I could probably replace 100 things on it if I had the money. Hell I'm not entirely sure it wasn't just that the jetting was just way too rich. Last guy must've been running an insanely lean mixture atleast 50:1
Anyway thanks for all your help through this cursed CR endeavor guys. I'll send you all a christmas card.
-
Just a thought here, the CR and YZ will probably bring in about 3-4 thousand max selling both, assuming you get at least 2 grand for each of them, I don't know how expensive bikes are where you live, but here in the US that 2k would be a bit of a stretch. Good luck with it though, if you get that 150sx I want to see videos
-
If you get a 150 youl want to drop a tooth on the front sprocket and swap the stock pipe for a DEP system, a friend of mine bought a 2011 and the thing used to get smoked by his 97 cr 125 but after just those two little changes the little monster can really haul ass.
Aslong as you can keep up with the gear changes that is lol I'm shocking on it after getting so used to a wide ratio gearbox haha.
-
Just a thought here, the CR and YZ will probably bring in about 3-4 thousand max selling both, assuming you get at least 2 grand for each of them, I don't know how expensive bikes are where you live, but here in the US that 2k would be a bit of a stretch. Good luck with it though, if you get that 150sx I want to see videos 
To put in in perspective: 2012 CRF250r is verging on 13 grand here. And I can flog my YZ250 to my next door neighbour hopefully. AS for the 125 I reckon I can squeeze 2 grand out of it easy. Weirdly enough If I can sell that 250 for what I'm planning on selling it for I'll actually make a profit lol. Hopefully I'll get about 4.5 for both at least I'll see how I go. Thats almost half way to the new bike and I can get some help from the old folks. But I might have to can my riding for a month or more until I can get hooked up with a job.
But whatever way you slice it, I'm getting the bike. Whether its in a month or in two, I'm getting it. And videos will come.
If you get a 150 youl want to drop a tooth on the front sprocket and swap the stock pipe for a DEP system, a friend of mine bought a 2011 and the thing used to get smoked by his 97 cr 125 but after just those two little changes the little monster can really haul ass.
Aslong as you can keep up with the gear changes that is lol I'm shocking on it after getting so used to a wide ratio gearbox haha.
Thanks for tip, I was gonna put a 50 on the rear and leave the front but I'll drop one on the front too. Aftermarket pipe was already a definite though I was going to go with a pro circuit. Apparently people have had issues with the FMF SST melting pistons or something.
Thanks
-
Thanks for tip, I was gonna put a 50 on the rear and leave the front but I'll drop one on the front too. Aftermarket pipe was already a definite though I was going to go with a pro circuit. Apparently people have had issues with the FMF SST melting pistons or something.
Thanks
I retarded timing a bit and upped the main to 185, no melt down, no problems with my SST.
-
Thanks for tip, I was gonna put a 50 on the rear and leave the front but I'll drop one on the front too. Aftermarket pipe was already a definite though I was going to go with a pro circuit. Apparently people have had issues with the FMF SST melting pistons or something.
Thanks
I retarded timing a bit and upped the main to 185, no melt down, no problems with my SST.
Really? Thats awesome I'll definitely keep that in mind, thanks man.
-
I like the SST quite a lot, now I'm running a Doma system which is almost identical to the SST. Overrev wise they are quite similar. I run the Doma with a 45/NP3/182 JD red needle set up and would jet for the SST at least 185.
-
I like the SST quite a lot, now I'm running a Doma system which is almost identical to the SST. Overrev wise they are quite similar. I run the Doma with a 45/NP3/182 JD red needle set up and would jet for the SST at least 185.
Thanks mate. What temperature is that in roughly?
-
Temps range from 30 to 35 degrees Celsius. Daytime.
click
-
You must be in need of a big bore bike just to carry all the water you'd need
. Our summer is usually about that but I'll have to richen it up when winter comes around.
Thanks mate. Oh and an update on the CR. Shop mechanics said they've got the water pump seal and countershaft seal on order. And they reckoned they couldn't get the plug to foul. They can't have been trying very hard but anyway. On the countershaft seal bit I wasn't aware it was leaking out there but apparently it is so they're gonna replace that too.
After that, we'll see how we go.
Thanks guys.