KLX 351s Starting Problems and Loss of Power
#12
08-11-2015 | 12:52 PM
Thread Starter
|
Senior Member
1st Gear Member
Joined: Apr 2012
Posts: 177
From: Houston, TX
haha, wow, that's definitely one of those little things most people would never think to check. If there was excessive wear on the piston rings and cylinder, there may be metal down there. That's a good point.
How hard would it be for OP to check that?
If I were OP I'd take that carb out and at least check the jets and float level. It's pretty easy to do and even a monkey can do it without breaking anything. Especially considering the slide won't need to be removed - it's the most delicate part I'd say. Check the numbers on the main jet. There's a small chance the mechanic is one of those "by the book, no matter what" kind of guys and put the stock jetting back in.
Based on your signature, that dj132 jet would seem awe-fully lean at sea level for a 351, you may want to consider going to a dj136 at a minimum. My stock bore 250 was running the 136 nicely on the top end (my cvk had mid-range fueling issues that caused overfueling in the mid-range though). Several other riders here are running jets larger than the 136 on their 250's at sea level as well.... anyway, check your current jetting, put in a bigger main jet if you can and test it out.
You might consider having a leakdown or compression test done before trying to dyno tune.
On a side note, you should really consider going with a mikuni when you can, OP
How hard would it be for OP to check that?
If I were OP I'd take that carb out and at least check the jets and float level. It's pretty easy to do and even a monkey can do it without breaking anything. Especially considering the slide won't need to be removed - it's the most delicate part I'd say. Check the numbers on the main jet. There's a small chance the mechanic is one of those "by the book, no matter what" kind of guys and put the stock jetting back in.
Based on your signature, that dj132 jet would seem awe-fully lean at sea level for a 351, you may want to consider going to a dj136 at a minimum. My stock bore 250 was running the 136 nicely on the top end (my cvk had mid-range fueling issues that caused overfueling in the mid-range though). Several other riders here are running jets larger than the 136 on their 250's at sea level as well.... anyway, check your current jetting, put in a bigger main jet if you can and test it out.
You might consider having a leakdown or compression test done before trying to dyno tune.
On a side note, you should really consider going with a mikuni when you can, OP
Last edited by Websurfing101; 08-11-2015 at 12:55 PM.
#13
08-11-2015 | 03:37 PM
Senior Member
1st Gear Member
Joined: Mar 2015
Posts: 283
From: B.C. Canada 2000' ASL
It's a bit of a long shot, but it sounds easy enough to check for. if it where a pickup issue you'd likely have stumbling and misfiring like crazy... or it just wouldn't run at all.
As others have suggested, check your bearing in the method described above and recheck to make sure your jetting wasn't changed - particularly the fuel screw setting that controls starting and idle (should be at least 2.5 turns out on a stock pilot jet and even that would be lean on a 351).
Last edited by pwjm; 08-11-2015 at 03:39 PM.
#14
08-12-2015 | 01:28 AM
Thread Starter
|
Senior Member
1st Gear Member
Joined: Apr 2012
Posts: 177
From: Houston, TX
I believe that I figured out the issue with starting and loss of power. I stripped the bike down and pulled the carb. What I found out is that the stealership that I took my bike to get worked on put a DJ 120 main jet in the carb. No wonder the bike did not want to start and had no power at all. They left the 38 pilot jet in that I am fine with. Pulled the spark plug too and the tip was white colored and looked like a bike that had been running really lean. Having Dynojet send me DJ 132 main jet to get this beast running again. I can't believe these morons installed such a small main jet and called it a day. They will be getting a nice Yelp review for not knowing **** about tuning modified motorcycles. They are suppose to be the pros, WTF.... Thanks everyone for your feed back.....
Last edited by Websurfing101; 08-12-2015 at 01:40 AM.
Thread
Thread Starter
Forum
Replies
Last Post