Top End Questions

[TheDocs400ex]

Ok guys, Ive finally gotten all my parts in for my rebuild (Wiseco 87mm 11:1, HotCam Stage 2, CRF450 Cam Chain, and Cometic Gaskets) and now its time to put her back together.

Is there any tips you guys would recommend? I've heard that "dry starts" are not good, so should I just lube everything with the motor oil that I'm going to be using or assembly lube??

As for my valves, they are coated in carbon, whats the best way to clean those? I don't have a valve spring compressor, but will buy one if necessary. How do I know if I need to replace the springs or not? I also have new valve stem seals, so I'm going to have to remove the valve springs to replace those, anyway, right?

I also got the set of cometic gaskets at a really cheap price, but they are 89mm... I didn't think that it would give me any problems so I went ahead and bought them. As long as I torque everything properly, should I be ok?

And for breaking in the new rebuild, how do I figure out the new jetting? And how do I break-in the new rebuild properly?

I believe that should be it...for now! lol thanks

[trailrider894]

Originally posted by TheDocs400ex
Ok guys, Ive finally gotten all my parts in for my rebuild (Wiseco 87mm 11:1, HotCam Stage 2, CRF450 Cam Chain, and Cometic Gaskets) and now its time to put her back together.

Is there any tips you guys would recommend? I've heard that "dry starts" are not good, so should I just lube everything with the motor oil that I'm going to be using or assembly lube??



Sounds like a good setup. I can only answer your question here, i would say that it wouldn't hurt to just dump a little of your motor oil that you will put into the quad onto the parts, obviously don't put any in the cylinder, but its a smart idea to give everything a little lube with your motor oil.

[togup]

A honda manual will answer most of you questions like the correct length of your valve springs how to check your valves for wear and torque specs plus a ton more helpful info. yes use assymbly lube ,see if you can borrow a spring compressor or go to the parts store where they lend them for a refundable deposit while you are there buy assymbly lube and a couple cans of brake parts cleaner to bust that carbon off your valves. As far as jetting goes ill let some one else wade in on that one i usually fumble my way through the jetting procedure

[DragonGunner]

I always lubed the rings, cylinder an sides of piston on assembly.
I use a cut piece of aluminum from a old liscense plate that almost goes around the piston rings, then tighten it enough with a hose clamp. This makes it alot easier an cheap way of putting the piston down the cylinder.
I lubed with the motor oil I would be using. You'll have a little smoke at start up till it burns off excess above the rings.

[CJM]

Buy some engine assembly lube, coat where the cam rides generously.

I like using 2 stroke oil, burns off a bit easier imho. I coat the cylinder, rings and piston.

To clean the carbon off the valves I used a grinder with a wire wheel. I made my own compressor but honestly its worth investing in the real tool.

To check the springs you will need a caliper, the service spec is in the manual-measure them and check. If they dont meet the spec its time for new ones.

The gasket set should be fine.

When you crank it over for the first time its a smart idea to have the killswitch on and just crank it solid for like 10 secs to lube everything up with motor oil from the tank. Remember now thats its been taken apart although the capacity is 2 qts its gonna need more since you drained out a bit more than you would using an oil change.

[sixer3]

I don't think you'll want to use that 89mm head gasket, just order an 87mm gasket, unless this is what everyone elses uses? I'm not really sure, i've only built stock bore and 440's (89mm)

I always lube my cams with assembly lube and a thin coat of conventional motor oil on the piston and cylinder walls, assembly lube on the wristpin, (make sure the circlips are in there all the way), after installing them take a socket about the size of the hole and gently tap it just to be sure, I've only had one fall out on me in like 15+ motors but it did a ton of damage. I check them everytime now.

for jetting if its a stock carb and assuming you have at least a slip on for a pipe and aftermarket air filter, I'd start with a 42 pilot, 2.5 turns ont he air screw, middle needle clip?, and a 170 main to start, you may go up or down here

[bherriman]

I always use assembly lube When I'm putting them together.


A wire wheel will clean up the valves nicely, but you'll need a spring compressor to get them out (which you need anyway for the seals)


As far as the springs go, if they have quite a bit of hours on them I always replace, even if they are within spec. Valve springs are often over-looked when doing a re-build, when they actually are one of the more important parts of your motor.