Project The Dying FZ

Well... sure enough this lovely *cough*junky*cough* bike found it's way to me as part of the honda trade. Sound quite sick to be honest, but it does run.

The sound it makes is hollow and it can't hold a steady idle, @MashtX did a bench balance on the carbies a while back but I have no idea what has gone on since then.

The bike blows quite a bit of smoke out the back, I'm suspecting the rings will need changing out if i can be bothered, the top end timing needs looking at and I have no idea about the head gasket.

See where it goes I guess... I'd like to put it on my spare 3LN frame but not sure about all the mount points just yet, will drop the engine out and do some measuring I think.

 

I like your enthusiasm haha

I'll have a look at the carbies again, they were clean before and pretty good condition. I think the top has to come off, I wouldn't be surprised if a new head gasket is needed but the valves definitely need some love.

 

First thing to come off was the horrible camo book contact... eww.

Did some digging into the top end and sure enough, all the clearances are out. I'm assuming, as I have no information, that given the exact similarity to the 3LN and 3EN's I have that the clearances would also be exactly the same. That is an educated assumption (seeing as with another "FZXX" I technically qualify for fizzer factory status) but I am very happy if someone would correct me. Going by that, particularly the intakes are out of spec... some almost no clearance. Most of the exhausts out by 0.1. And as it usually goes, I'm 5 shims short again, how frustrating. I have a growing pile of them that I'll never use and nobody ever seems to have any to swap! /rant I'll get over it. Might call some bike shops and see if they'll swap me 2 for 1 or something...

Also I think the carbies need a sync...



Here are a few more photos.


If anyone knows where I can source a reasonably priced dash, it needs a replacement. some crappy chinese speedo, temp gauge and wires for the tacho are just hanging in mid air. Also the headlight glass is smashed so I'll need a new one. I tried to see if the 3LN front would fit but it won't without welding, shame because that headlight would look better.





Frame is a bit ratty but a clean up should have her looking better.



The magneto has the T mark on the side of the wheel itself which is equivalent to the 400. There's no marking on the inside of the casing like the 3LN and my suspicion is that it's the engine casing split again and that's what I've gone by. I checked the lobes and pretty comfortable I'm getting TDC at the corresponding places on the casing.



The top end has all the markings similar to the 3LN which is handy. I've never done a 2KR so I don't know if they're much different but the dots on the end of the cams all match, including the cam chain design, cover, cam covers etc.



I compared my 3LN cams to the ones in the top of this engine and they are EXACTLY the same. i wonder if that's why it runs rough... anyone got pics of 2KR cams next to 3LN ones so I can compare? Or are they expected to be the same? There's very little information on the phaser out there that I can find.

3LN on the left, phaser on the right...

 

So this is interesting. Despite the optical illusion the CCT's are exactly the same. Looks like someone had stretched the outer spring on the FZ (bottom) probably to compensate for tension loss and comparing to the 3LN (top) it is also missing it's inner spring. I'm going to put the 3LN one on with the two springs, as the one from the FZ is buggered.

 

I hope not. I really hope not...

But it was a bit uhh... "loved" by people who I don't think knew how to love...

 

Careful Khaiden, I reckon this thing will beat your 2KR when I'm done

 

LOL we'll give it a go, it's basically a 2KR anyway so it's all up to the skillz of the rider!

(course as I'm a fatty that will work to my disadvantage...)

 

Well, trying to make a dent in this now. Got the head back from the shop with 2 new threads tapped (2 & 3) and 1 & 4 cleaned up. Also had the base machined flat, cost around $120 for all that which I thought was a fair deal.



I spent some time studying my new FZR250R head gasket and comparing it to the one that came off the FZ. I swear they are EXACTLY the same. The FZR gasket is completely covered in black material which would be designed to form a seal. There are grooves and areas that compress down when the head is tightened like you'd expect, and obviously with the heat of the engine etc the FZ gasket is a little "stretched" in appearance as it has been torqued down before.

So this is where I had a naughty thought. If I could replace the sealing material... it might cause an issue or it might not... so I decided to test the theory because if the bike starts getting water in the oil I'll just shut it off and strip it back again, no biggie and if it dies... it's not a big loss.

So I spent some time with a stainless scourer getting rid of all the old sealing material.



I then used the copper gasket cement rather thickly on both sides to try and replicate the FZR250R coating.



It came up pretty well considering. I would hope it is enough to not cause any problems but we'll see.



once you paint it you have to put it together within 45 minutes or something so I got straight onto it.



So all the timing was done and then... binding. Bugger. Taking it all apart again and lo and behold...



This was in cylinder #2, one of the new tapped threads. Maybe I just tightened it a bit too deeply. Once the cams were off again and the plugs out the motor turns over fine but I'm gonna have to watch that one the second time around. For the piston to hit it it must be quite a bit deeper than desirable...?

 

I don't actually know, I just asked them to skim it flat. It may be that it has been done in the past and now it might be out of spec. I removed all the plugs and tried again but it's still binding so the piston(s) must be hitting the valves. I'm really struggling to time this engine which is unusual as it's basically the same as the FZR which I've done more times than I can count.

I think the head will have to come off and I'll need to check what's going on. Can't be bothered now though, might look at it again over the weekend.