Engine Work!!!!!!!

[atvracr350]

i ordered a 11:1 standard bore piston the other day and am about to get that a stage 1 or 2 hot cam haven't figured that out yet and i was wondering, do i have to hone my cylinder or just get the piston installed? and also should i go ahead and get a sparks timing key installed or no? do they make that much difference? thanks for the help

[hondafox440]

No, you shouldn't have to. Just make sure to crosshatch the cylinder with a scotchbrite pad at 25-35 degree angles to ensure proper lubrication.

[44oEX]

yeah what he said.

get the stage two cam and don't get the ke you with hi-comp it will run to hot.

[atvracr350]

ok thanks guys do you know if i should have anything else done while im in my engine? i am on a limited budget and am not going big bore so that is out of the question.

[beak7707]

I would go ahead and hone it, it would only take a min to do. It will help set your rings much better.

[atvracr350]

thats what i was thinking beak i figured while they are right there just go ahead and hone it just to make sure.

[cals400ex]

yep, hone it out for proper ring sealing. also, have them gap the rings to the cylinder while they are at it.

I got a 3 angle valve job for 50 dollars. It won't make the bike much faster, but the carbon won't build up as fast. :D

[Knips178]

Just get it honed. I just go mine done for $10 at a local shop. It may make the difference of you taking the engine apart later because your blowing blue smoke. just don't eat lunch for a day or two and take that money to get your engine running right.;)

[PHIL_B54]

Originally posted by golfman400ex
I got a 3 angle valve job for 50 dollars. It won't make the bike much faster, but the carbon won't build up as fast. :D

not to flame or anything, but the 400ex comes with a 3 angle valve job from the factory, so unless your valve seats are shot and hurting your preformance, you will not go any faster. ive never heard the carbon thing???

[Knips178]

Polishing will help carbon buildup, but yeah the stock head comes with a three angle valve job. I have heard that unless your quad is maxed out with engine performance parts, the porting and polishing doesn't help much. The only real advantage is that there won't be as much carbon buildup over time.

[EXDUNER127]

Porting the head does give you power, if you have a aftermarket head pipe, porting the head can benifit more air, and if you get a carb too, you will benifit even more...My engine builder Kenz cycle tech in AZ says he can give me a 10% power increase with his port job. And he makes some of the fastest bikes. He will beat sparks at next years 4stroke wars. And sparks was #1 engine builder.

[Knips178]

yeah, what I said. Unless you have alot of Performance parts in your engine, the port and polish won't do much. you have alot done (fcr carb, full exhaust, etc) so it would help you, but for a stock motor the gain would be next to nothing.

[EXDUNER127]

Yah i thought we were on the same sublect with him wanting to know what else he could do to compliment his cam and piston.

[Knips178]

I apologize! I'm just saying, I think there are better ways to spend his money to get more power.

[wilkin250r]

When you hone the cylinder, it basically scratches the cylinder in little cross-hatches. If you look at it under magnification, there are sharp little bumps in a specific pattern.

During operation, your piston rings push outwards against these little bumps, and they act as a file against your rings. This gets rid of any imperfections on the surface of your rings, ensuring a tight seal. These little bumps aren't near as hard as a regular file, so they wear smooth very quickly.

So, in essense, by honing your cylinder, you get your rings to seal very well by basically filing against the rings. However, they wear smooth very quickly, so it doesn't keep filing your rings down to nothing. This is basically the break-in period of your piston rings.

In a nutshell, yes, you should hone your cylinder. There is no point in getting a high-compression piston if your rings don't seal well against the higher compression.

[atvracr350]

ok thanks guys for all your help, i determined i was going to get my cylinder honed.

T
not to flame or anything, but the 400ex comes with a 3 angle valve job from the factory, so unless your valve seats are shot and hurting your preformance, you will not go any faster. ive never heard the carbon thing???

The reason 400ex's come with a 3 angle valve job is to keep the carbon from building up on the valve seats. If the seat becomes flattened over time, the increased surface area will allow carbon to build up on the contact area between the valve and the seat. This in turn will create an imperfect seal and therefore cause compression loss. Race bikes get 5 angle valve jobs to further decrease the contact area with the valve and thereby decrease the opportunity for carbon to build up. I believe that if you are interested in long term reliability, a simple 3 angle valve job is a must every time you remove your head.

[PHIL_B54]

im just saying that some people a led to believe that a 3 angle valve job with their headwork will help ADD power. but it isnt that you are adding power, it had it from the factory, but that you are re-freshing it.