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I decided to build up my spare engine

3104 Views 53 Replies 9 Participants Last post by  King_Panther13
I created a thread about this a few weeks ago, asking if I should use my spare engine for parts and build up my current engine, or build up the spare and then just swap. While it'd be most logical to just build mine up, I decided that the most convenient option will be to just build up the spare, as everything that it needs done to it is something I would do to my current engine anyhow.

Now, I want to know if I have the right idea of what all to do with it. I want to make it as perfect as I can. I know that these engines don't take kindly to modding, so unless I find some easy mods that have little risk to negatively affecting my performance, it'll be a stock rebuild.

So far, my list of things to do/get is:

Gasket Kit

Mechanical Seal

G8 Stator

Cam Chain+Tensioner

Piston Rings

Lap Valves

Inspect entire engine, and decoke everything possible.

Clean out and/or replace oil pump

New clutch kit, if current one isn't serviceable

Is there anything else that I should consider, or did I pretty much nail everything?

Oh, and there was a bit of rusty water that came out of the cooling pipes when I removed the radiator. I was told that this can be flushed out after the engine is rebuilt, and put back on the bike. Is this true, or can I get it flushed out before putting it on the bike, so I can get it "perfect?"

Thanks for the advice. This is still a bit off in the future...but the first thing I'm going to do is get the heads serviced (the valve lapping and whatnot) and get my gasket kits. Then I'll slowly do everything else until it's ready.
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Shep, would you suggest use of this Moly Slip stuff in my rebuilt FJ engine (sorry to Hijack!)? I re-honed the bore and installed 2nd hand (low hours and mileage) high comp pistons and rings.

Also in my CX and running FJ?

Cheers, Matt
Cheers Shep,

The daily rider FJ is a little over 70k miles. It does smoke, especially when it gets cained but I expect its those valve stem oil seals as they're notorious on these engines for drying out. Especially when they've been stood like this one had before it was mine. Bores and pistons are generally very tough on the FJ, I know living examples that have done more than 175k on the original pistons and rings. Bit like the CX engine! Tough as old boots!

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Ok, so an intial top up of 240 ml then 120 ml from then on. How often tho? At oil change intervals?

Cheers for the info.
To answer both.Just add 120 ml for your FJ at oil changes after that initial 240 Ml and it's an engine additive so just stick it in the oil

Convenient that I'm just due for an oil change on both bikes..

Cheers Shep, much appreciated. Sorry to hijack the thread.
Cheers man, had a look at Sheps link, its quite cheap too so its all good.

With regards to your cylinder head fasteners, I would expect them to be reasonably tight but not socket-breakingly stiff. I've never had a CX engine apart but when I did my FJ engine, I used 18" long, half inch drive breaker bar whilst my friend held the thing in place on the bench.

I wouldn't expect to do them with a cheap socket and a normal sized 1/2" drive ratchet tho. Please don't get me wrong, I'm not saying you have poor tools but having the right ones makes it much easier.

Good luck.
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Your torque wrench should be more than adequate, sounds like them pins bloody tight!
Best tell Simon I never used his cheapy torque wrench as a breaker then.. Whoops!
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