Now that I have my Xplorer 400 all rebuilt and tuned up, I guess I have one last question (hopefully). I decided to go through my machine because it is 19 years old and has a touch over 5,000 miles on it. An older gentleman owned this machine a majority of its lifetime, so it was well cared for and not beaten to death like many of the liquid cooled 400's I see out there. Everything on this machine was still stock, the piston, the brakes, and all the gaskets. I replaced all the seals and gaskets, rebuilt the engine and the carb and replaced the bearing for the waterpump. I have about 2 hours of time on the motor and the counter balance oil is just as clean as it was when I put it in. My question is, since this machine is this old, should I look at replacing the reeds? They are still original, but since I am not familiar with two strokes, I didnt pay much attention to them when I took them out and put them back in. I just sprayed them off with carb cleaner and put new gaskets in. I think I might have noticed that they might not have been all the way flat against the reed cage, but I'm not sure. Ever since I owned this machine, I noticed inside the air box, right before it goes into the carb, that it is always slightly wet with fuel. I just figured this was normal for a two stroke that vibrates. It has been doing it for some time, because the air box is stained where it is wet from the fuel mixture.

P.S. This machine starts fine, in my opinion, but I'm told a symptom of bad reeds is hard starting.

Thanks,
Mike

 

Wouldn't worry about the reeds unless you really have a big air gap at the ends.Not recommended to flip the reed pedals over either as all that does is put stress on them and they can split or break off.Rarely ever had a problem on the 350/400 stock reeds.I've installed aftermarket reeds such as Boysen for customers and didn't notice that much of a difference on a stock engine. Wet area at the air box opening could be from the carb vibration which the 400 is noted for.Should have the rubber dampener under the carb, mounted on the transmission to help block some of the vibration and fuel spray.Plus a float arm out of adjustment,needle and seat wear are common things to keep up with on this engine that also can cause some fuel spots in the air box neck. If you haven't rebuilt the carb might be time to install a carb kit as cheap as they are. Plus here's good instructions from the manual on carbs and adjustments. You have the VM34 Mikuni.https://www.google.com/url?sa=t&rct=...,d.aWw&cad=rja

 

Thanks OPT,
I have rebuilt the carb and everything looks good as far as the rubber block under the carb also. I was just curious about the reeds because I was not sure if they are a wear item. I know the process of a two stroke firing cycle makes them move (pulse) so I didnt know if they got brittle or warped. I'm not familiar with two strokes, but I remember my dad having problems with his chainsaw running rough and the chainsaw dealer did something with the reeds and I thought they said they wore out, but that was 30 years ago and I cant remember to pack my lunch most days let alone remember what my dad did to his chainsaw when I was a teenager, lol. All I can find for reeds out there are ones like Boyeson and such which are more geared towards guys who want to have more power. I am completely content with the power of my 400 for what I do, lol. I just want reliability, not wide open throttle. My machine usually just goes out to the woods carrying a chainsaw, cruises the campground when the kids are driving it and rarely sees 30 mph when we go on trail rides.

If I have some time I will pull the reeds out and check them for warpage and if they are ok, I will keep running them.

Thanks,
Mike

 

Stock reeds are actually stronger than many aftermarket reeds simply because they're thicker in most cases. I've seen a lot of Boysens,etc snap/split pedals because they're thinner.To pay for a quicker response means they have to be thinner and softer.

 

So, basically the aftermarket reeds just let the motor rev quicker and are more prone to cracking over time? I guess on a machine like this, I would sacrifice a little power for better drivability. I could see on a sport bike where it's operating at higher speeds, but on a workhorse atv I don't think it would pay to put the aftermarket reeds in. My brother in law has a 1999 scrambler with the two stroke 400 and it's all hopped up with an aen pipe, boyeson reeds and some other mods. He brought it to our campground once but it didn't really impress me much because there really wasn't any place he could open it up so basically it was a loud and smokey toy. He did take it out to a swamp behind our campground and proceeded to bury it so my old Xplorer had to come to the rescue anyways, lol.

Thanks,
Mike

 

On a work horse atv,no not needed. On high performance cycles and atvs then yes worth the cost,plus most of them already have them installed such as V-Force,Boysen,etc.The thing is on a stock machine you may benefit a little such as a little quicker response,but where they really help is with other modifications that go hand in hand such as porting,different carburetion,free flowing exhaust systems,more open air filters,then you've lost the work horse atv you had before.