All your bearings and a arm bushings will be the same way to check them as described in video. Take a compression checker and pull the spark plug out of the top end, screw the comp gauge in and kick it until it quits raising the gauge. Not exactly sure where a healthy psi range on compression is on a blaster. Should be able to find it on an online forum
Looking to buy a used 400ex pretty soon, barrings steering and things like that won’t bother me when buying what I’m most worried about is not doing enough research and buying one that runs but will break down in the near future. What are red flags to look for in that situation?
Lots of engine noise, they are a little noisy anyways but if it’s really loud that’s probably timing chain slap. Or if it smokes any at all it probably needs rings or valve seats. If you have to do those things you’d be better off doing a whole top end
@@wheelindylan6138 Thanks a lot man. Also, I see quit a few in my area going for $3.5k - $5k all claim to run great, is that a good price range for these or should I try negotiating?
@@dondada4470 right now the market is up. In my opinion you’re better off to spend a little extra to get that extra clean low hour quad! The 400 is a very tough Atv and a lot of them have been through a lot of abuse over the years. If you use this video and everything checks out you should be looking at a really nice unit
@@lixszdil2301 they have an issue with the clutch baskets exploding. If you get it change it out with the 09-10 basket, it’s much stronger. All the parts you need are on the forums. Also make sure it either has a vortex ecu or an ecu reflash. They run incredibly too lean from the factory. Other then that they are solid machines! Run a good case saver too!!
@@wheelindylan6138 okay thank you! I’m kinda new to Yamahas, this would be my first one and I don’t want to be on the trail and get f*ked. The one I’m looking at doesn’t come with a vortex ecu but I’m definitely gonna buy one, would it mess anything up if I ran it without one for a while? Or just less power? Because I don’t know how to tune it.
@@lixszdil2301 if it has a stock exhaust and no tuner it’ll be fine for a while just won’t run as good as it should and the header will get really hot fast. If it already has an aftermarket exhaust I would get the vortex pretty quick. BNR racing can flash the vortex to whatever tune you need depending on intake setup and exhaust. Then you won’t have to mess with it unless you do motor work etc
