[D_morris76]

I just got a raptor 700 that I bought in none running condition. The neutral switch sensor was bad so I started their and replaced both the neutral and reverse sensor and I got the bike to turnover but it was slow cranking so I pulled the starter and did a bench test and it sounded like it was at the end of its life so I replaced the starter and solenoid. After I replaced that the bike slowly cranked over a couple times and then cranked as should and ran for 10 seconds and died. It sounded healthy when it ran for the 10 seconds. But we are back to a slow crank and it sounds like it has a bind somewhere. But when I pull the plug and crank the bike turns over much quicker as it should. Do you guys have any ideas on what if could be?

 

[D_morris76]

Also I have checked the timing and it isn’t out of time. I haven’t looked at or messed with the valves yet.

 

[morphrider]

How is the battery and spark plug condition? Is this a completely stock bike?

 

[D_morris76]

Battery is fine I have another raptor I know the battery is good in so I tried that one too and spark plug is fine even just put a new in it

 

[D_morris76]

Bike is also stock

 

[Aluminum_Owl]

What year is it? Check connections on positive and negative battery cables (where they connect to main fuse block) pop in a new fuse while you're there. They are cheap. I would also check valves for sure! Thumpers are notorious for not wanting to run if the valve lash is tight.

 

[D_morris76]

It’s a 2006 a had already checked the cables put in a new fuse I will check out the valves and see if they need adjusting I feel like it’s possibly the valves at this point but just wanted to check and see if anyone else has ran into this similar issue

 

[Aluminum_Owl]

It’s a 2006 a had already checked the cables put in a new fuse I will check out the valves and see if they need adjusting I feel like it’s possibly the valves at this point but just wanted to check and see if anyone else has ran into this similar issue

Mine is an 06 as well. I had a "similar" issue. Mine would start fine but once it warmed up it would stumble and sometimes die. But totally intermittently. It would do it more if I was riding on rough terrain. After testing every sensor and component I figured it had to be a harness issue. I put in a new year 13-14 harness and now it runs like a new bike. I'm hoping your issue is something simple. Valve adjustment is a good place to start...then maybe tps position. These 06 had a few issues being the first year with a complete new system. Good luck

 

[D_morris76]

yeah I’m gonna start with the valves thanks for the info tho I appreciate it

 

[CantFeelMyLegs]

Have you done a compression test? Does it have an aftermarket cam? Could be a long shot but maybe the auto decompression isn't working. Valve lash will be different with different cams too

 

[D_morris76]

As far as I know it’s the stock cam I haven’t done a compression test on it yet it seems to have good compression. I was also curious if that was a possibility I know the 660 raptor had issues with decompression pin but I wasn’t sure if the 700 had a similar set up that could fail or what

 

[CantFeelMyLegs]

If the decomp isn't working, could be the cause of the motor cranking slow due to not being able to easily overpower the higher compression. I think stock compression is under 70ish

 

[D_morris76]

Do I did a compression test and adjusted valves the intake valves were a little loose so I adjusted those to the manual suggestion the compression test came back high it was putting out about 79 and the manual says it should be around 64 would that be high enough that the auto decomp isn’t working?

 

[CantFeelMyLegs]

Not to sure. Seems like it's working, just not within yamaha specs. I don't think 79 is to high to cause slower cranking.

 

[CantFeelMyLegs]

Just watched a video by 2 vintage. He was working on a yfz450 that was slow cranking. He found rust in the kill switch/headlight switch block. Cleaned out the rust with wd40, worked the switches back a fourth a few times, and slow cranking went away.

 

[D_morris76]

So it doesn’t always slow crank it will crank over 3 times with the spark plug in then have a slow crank. It also cranks fine with spark plug out. Since the decomp assembly and pin are so cheap I’m going to replace it anyways and see what happens. If it doesn’t work I will definitely be checking out other options

 

[SnowCamo]

I know you said you checked the battery cable, however battery cables look good but fail a load test with flying colors. Have you noticed any change in starting rotation power with jumper cables connected?

 

[D_morris76]

I haven’t tried tried jumper cables But I did replace the power cable and cleaned off were it’s grounded