Is this possible??

[red400ryder]

I'm gonna rebuild my motor cause i have put alot of miles on my baby, it wouldn't surprise me if i have more than 4000 miles on it but my question is this.....my motor was blowing blue smoke..not really too much and awfully bad but it was there..i could only see it at night real good but during the day it is not noticeable to me....when i took my motor apart i had carbon buildup on the piston...but before i tore the motor down it never seemed low on power..so what i am asking is that since it didn't seem low on power cause it seems pretty strong..it probably doesn't need new rings cause i have read that you need new rings when you lose compression or loss of power...so when you are blowing blue smoke and you can smell oil burning while you are riding and once you stop...does that automatically mean you need new rings in your motor even though the bike still runs strong...couldn't valve seals be the problem instead?? sorry for so long just trying to get my statement out..i appreciate any feedback..thanks..later madmike

[Texan32]

It could be the valve seals and/or the rings. Did you ever take a compression reading? If i were you, i WOULD spend the extra few bucks and get a new set of rings. They aren't that expensive and it just a extra security. What i'm wandering is why don't you do yourself a favor. Since you say the motor has a few miles on it, why don't you throw a high compression 406 kit in there. 406 os just a .40 over bore....don't worry about it. The ex can handle up to .120 over bore. But thats jst what i would do....since its already apart and all.

[rummerd]

Yep, you must have planned for a rebuild if you took it apart, could have just run it for free. So, you need a piston and rings anyhow, and you probably should have it bored, so the 406 idea sounds like a winner. While the head is off, might as well have that looked at for a valve job, maybe a little clean up on it as well.

[red400ryder]

yes, i am planning on getting new rings for the motor and new valve seals. Also I'm really not looking to get a bore kit of any size for my 400. I am gonna keep it at stock bore and i ain't planning on getting a higher compression piston. I'm just rebuilding the motor back like it was(stock) and adding a pipe afterwards. So, if anybody can tell me everything that i should do before the rebuild such as: should i get it bored and sleeved, Valve job maybe, stuff like that. I'm not going inside the engine for any performance gain cause it ain't that big of deal with me. I would appreciate if somebody would let me know what all they think i should do in regards to my plans for the motor i have stated above..thanks for any help i recieve..later madmike

[rummerd]

It sounds like you just want to "freshen up" your motor. No problem, order a stock piston kit (service honda has great prices) and put new valve seals in. Should be good to go. Might want to have a machinist check your bore, but probably would be a waste of time. The 400 is pretty reliable and you should be good to go with a stock sized piston unless it or the cylinder show a lot of wear. Four hundy's make good fun power with just a pipe and a jet kit.

[Texan32]

Red,
Re-read your last statment. First you say you don't want to get "a bore kit". But a few lines down, you ask if you need to get it bored or sleeved. I'm not trying to rag on you man, but i don't get the feeling that YOU should be doing anything to the inside of your engine. Just from the statments you have made, i'm afraid that you might cause more damage than good.

Quick lesson:
The STOCK cylinder can be bored (cut) up to 3 times. .040over making it a 406, .080 over making it a 416, and .120 over making it a 426. THAT IS THE STOCK SLEEVE. The only reason you would need to resleeve the jug is if you 1. have already bored it .120 out and need to rebuild the engine again, 2 have scared the cylinder too deep to where a bore job won't work, 3 you install a BIG BORE KIT.

I am going to recommend that you let someone else to the work. But is you insist, here is what you need/need to do. Have the cylinder inspected by a machine shop. They should be able to tell you if you need a bore job or is a honing will work. (honing is just smooth sanding the cylinder...retains standard bore). If you DON'T need to bore the sleeve, you DON'T need a new piston. A new set of rings will do just fine. It would also be a good idea to have a valve job done on the head. With that valve job, i would get a set of Viton valve seals and have those installed. You should look into getting a gasket kit as well. DO NOT reuse the head gasket...get a new one. I don't care what anyone says, its just add security to get a new gasket. You also need to find yourself a good torque wrench. Appling the proper torque to the head bolts is VERY critical. Also, you need a set of feeler guages so that you can adjust your valve lash. There is a great do it yourself guide for setting valve lash in the "ex tech" section.

Hope this helps. Good luck.

[red400ryder]

Rummerd
Yeah you're spot on for what i am gonna do...i should of just said that to begin with so we didn't go through this whole ordeal..thats my fault..But yes i am gonna refresh my motor and probably add a pipe to get alittle more pull. thanks for your time and help..later madmike

Texan32
I know what i said in my statement that i ain't wanting a bore kit and then i asked about getting one...but only why i did that was cause no i don't want one and second if i have to get it i might as well know so its better to ask for help than not to ask at all if your stuck on something you can't figure out...and also i can see why you say i shouldn't be in the engine but let me assure you that i wouldn't be going inside it if I didn't know what i was doing...i ain't no mechanic or nothing but i know whats what in a motor and how it works and such..so don't worry your heart out on me i will be fine...also i appreciate the quick lesson..always good to learn new things that might help later on...and also thanks for going through the trouble telling me all about everything i have to get done since i did insist...even though i already knew everything that you took the time to tell me again..but i appreciate you reminding me...well last but not least..i thank both you and rummerd for your help since you are the two that gave me feedback..well thanks guys for everything and i think i have enough info to get to work...later guys..thanks again..madmike

[Texan32]

Not a prob guy. I just didn't want to see a good quad go down:p Hope the rebuild goes well.