My Clymer came yesterday, and the first thing I did was check to make sure the numbers given to me for the tolerance on the lower rod bearing were correct. The specs were but the wear limit says 1mm . Could I get a weekend or two of riding out of it, I measured it at .66mm a few weeks ago and haven't touched it since. If I were to ride it, what could break? I already planned on new crank and main bearings, is there anything else that could get fudged up beside those things, like the cases maybe? I fast response would be appreciated.

 

Are you referring to your side clearance between your rod and thrust plates?? If so, you don't have a problem.

 

Yes I was, guess I should have clarified that. Thanks alot KNOWSALOT you have been very helpful.

I forgot to ask, are K&S gasket sets any good? I think it was lonestarbanshee who was having problems with the head gasket not sealing.

 

well if your rod should happen to go depending on how bad your lower bearing disengrates you could push out your lower cases and make virtually impossible for them to seal properly again.i've seen alot of cases get massed up when the lower rod bearing goes.theres is only a couple of millimeters of clearance at best between your rod and the cases in the bottom of your crankcase.
so if you have any second guessing of the condition of your crank and rod bearings i would suggest replacement .

 

Can anyone answer my question about the K&S Gasket sets? There is no up and down play, but side to side play. I have another question, whats up with the break-in procedure and piston replacement. It says to ride for 50 hours I think to break-in the top-end, but says to replace the piston and rings every 30 hours. Is the 30 hour piston replacement another one of those things Honda has to say to get out of piston replacement beyond 30 hours of use?

 

Break-in will depend on whether you are using a cast or forged piston.

The 30 hour piston replacement is a safe guard used by Honda and others to keep the engine within OEM spec. at all times

These aren't from a manual, but what we use.

On cast pistons, mixture ratio at 30:1 for the first tank of gas. Altering speeds for the first tank of gas. Run no more than 20 minutes before shutting off for an engine cool down.

On forged pistons, mixture ratio at 30:1 for the first TWO tanks of gas.
Altering speeds for the first tank only. Run no more than 15 minutes before shutting off for a break, not a complete cool down.

Those mixture ratios are using Golden Spectro. Ratios will vary on type of oil you use.

I don't know about the K&S gaskets. We use Cometic only....Sorry.

 

Thanks for the break-in tip, i'll be sure to do that. ART pistons are cast, correct? While you're talking about break-ins, I have some questions for you. I found a break-in procedure at offroad.com/atv and it says to mix your oil/gas at the ratio you would normally run. I run Golden Spectro at 50:1 normally, while you say to use 30:1. I beleive that break-in sheet was provided by Duncan Racing. One last thing, I bought a piston with an anti friction coating, and there is a total of about 5 minutes of idling on it, and the coating is already wearing off pretty bad, whats the point of having it if it wears so quickly?

 

The coated pistons really don't do anything different from a standard piston unless the cylinder has been converted to a nikasil cylinder coating. If you are still using the stock type cylinder, the coating will wear off and is nothing to worry about unless the wear is also getting the piston itself.

We use Spectro 50:1 also, but use it 30:1 during break-in procedures.

I'm sure the reconmendation by Duncan works, I don't dispute that. Maybe we are just more cautious and don't take chances for something to go wrong.

There may be ART pistons that are forged, but all I have ever seen from them is cast.

 

ltracerx;
When you say the motor has idled, I hope you are "blipping" the throttle the entire time the motor is running. If not, you run a HIGH risk of siezing the motor.

By blipping the throttle you are effectively;
1) making sure you get a a good mixture of fuel AND oil to the piston and cylinder and
2) getting sufficient coolant flow to the cylinder which won't happen at an idle.

 

Well, the first time I started it up after the new piston, rings, and bore, I let it idle for about 1 1/2 minutes without blipping. I noticed a coolant leak so I retorqued the head nuts and started it again and this time I "blipped" the throttle a few times for about 1 minute but the noise was still there that I thought I was taking care of by rebuilding the top-end, so I shut it off. I noticed on the cylinder the other day that there is more wear on one part of the cylinder than anywhere else, could the rings have moved during installation and caused this or is that somewhat normal?