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Yea, an awesome guide, it would make a good tutorial thread, whilst its not a mini head, it has all the same principles. I know it'd come in handy for me if I was inspecting a used head.
 
Yea, an awesome guide, it would make a good tutorial thread, whilst its not a mini head, it has all the same principles. I know it'd come in handy for me if I was inspecting a used head.
There is still a little to come, Then i will maybe (depends on how much time i have) will make up some diagrams etc.. etc.
Really this process should be done every service but i will probably do mine every 450hrs approx... depending

I should have some spare time this weekend since i have to wait till payday for new parts :p Also some new tools would go far some $$ will have to be spent to get them to spec

Maybe have another spare head soon.. SSvalves though But its good ot have a spare if its at the right price.
 
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Here is a picture of one intake valve... You can see the shiny part of it is the 45 degrees, or the sealing surface. This is the area i will be focusing on this post.. This will be quite a easy thing to do while you "bang in a new top end" youd be suprised how many people (not mechaincs) do not bother to do this.. i have even heard stories of never checking valves for years...

Anyway, now the valves are removed from the head all in order (i like to put the head upside down on the table with the cam chain side toward me then lay them down in order infront of the head)
grab a sharpie (or blueing if you have any) this is the "no tools method" that i will use...
Coat the entire valve, or valve seat your choice in my case i coated the valve.. now while its wet push the valve into the correct position on the head and push it down and spin it a couple of times..
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Here is the coating left on the valve seat, note not a good example the sharpie dried a little before i did it i did this again afterwards but forgot to take a photo of it..
This gives you a good idea of where the valve is coming in contact with the head.
There are specifications in the manual of how much surface area there is meant to be, or the whole 45deg angle to be safe..
Also look at the valve and there should be a clear surface where the sharpie rubbed off.. this is the contact area that the valve uses for sealing and also cooling. If this area is compromised in any way eg.. carbon dirt etc this can cause the valve to over heat and damage the seal etc then cause more damage to the motor.
I always check this area of the valve before i re-use it.. thankfully mine are looking good (at 130 a valve there not cheap to replace) My seats could be better but a may lap the valves in to correct them (They are ti valves with no coating) not sure if im meant to or not? but there leaking a bit so i want too.

Time to clean as im waiting for the $$ to buy some parts
before
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Some elbow grease later:.........|
..
..
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After:

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Some good stuff right here

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Okay a recent development.. After test jigging up pretty much the whole motor i have come to find the nice shineyish crank to be from another bike.. the dented and nasty one Is the only one that would have come with the bike..
What makes me say that?
The right hand side where the drive gears fit on have a different spline assembly, the nicer one coming from a wr 400 (with a 426 rod) that could be usable but the different drive assembly means i would have to buy almost the same value as the new crank in gears and other fittings..

The current rod on this crank seems usable but the death of this motor was a piston breakage the rod is straight but does have one minor mark on it But for the extra $150 id prefer to wait and put that into it before i put the cases back together..
 
Okay a recent development.. After test jigging up pretty much the whole motor i have come to find the nice shineyish crank to be from another bike.. the dented and nasty one Is the only one that would have come with the bike..
What makes me say that?
The right hand side where the drive gears fit on have a different spline assembly, the nicer one coming from a wr 400 (with a 426 rod) that could be usable but the different drive assembly means i would have to buy almost the same value as the new crank in gears and other fittings..

The current rod on this crank seems usable but the death of this motor was a piston breakage the rod is straight but does have one minor mark on it But for the extra $150 id prefer to wait and put that into it before i put the cases back together..

Hang on I remember someone a few months back telling me that buying a pit bike would rob me of all my money.....

That sucks mate!! So much money, hope you end up better off than buying one but the experience is surely good :thumbup:
 
Hang on I remember someone a few months back telling me that buying a pit bike would rob me of all my money.....

That sucks mate!! So much money, hope you end up better off than buying one but the experience is surely good :thumbup:
Buying one well a "good one" and then prepping it completely for what i want it to do reliably (with almost 0 chance of issues) would have been damn near impossible imo (as because these have been known to be bullet proof from factory.)
if i was lucky enough to find one that was all in spec and with the larger tank incl roady gear etc then id be expecting from 3k to 3.5k (of same year level)+

This one was $650 including a stand (a nice one at that)
I will be putting in around 1.4k into the motor +linkage bearings, total price $2050 (not including labor for machining)
About $425 into seat, and tank (shiney and new and not bound to split anytime soon) total: $2475
+ new dot approved front tyre (Around 120 each) Total:$2595
Lets say it costs me 170 in labour to get all the gears back cut and the new rod pressed in (still going to run the old crank halves) Total $2665

Then go out riding until the 300 hr mark and know your not going to have transmission,bearing,week end wrecking problems $Priceless

Time spent assembling is nothing to worry about because when i know i have seen it, measured it then its 95% less likely to fail unexpectedly is worth all the hassle.

Then i could also go out ride it for 300 hrs, wait a little bit and advertise it and sell it for around 3k or 3500 if i tried really hard.. however i don't see that happening at the moment unless a really nice cheaper new wr or exc 300 comes up Time spent without a bike to ride is driving me nuts though that gives me motivation to scourer for more parts and clean everything looking for minour issues..
 
Sounds good!! Suppose you dont have to buy everything at the same time too.

Not so sure about never getting a pit bike to be 100% reliable, no bike is 100% reliable....My bigwheel is pretty decent atm, needs the bushing done in the rear shock and she's sorted until I find a new manifold. I guess it depends on what you're happy with clearly you want something able to be registered and reliable. At least you'll know how to fix it if something goes wrong!!
 
Mate, I think rebuilding the bike and knowing what makes your bike tick is half of the satisfaction in motorcycling.

Sucks about the crank though. Loving this thread.
 
Sounds good!! Suppose you dont have to buy everything at the same time too.

Not so sure about never getting a pit bike to be 100% reliable, no bike is 100% reliable....My bigwheel is pretty decent atm, needs the bushing done in the rear shock and she's sorted until I find a new manifold. I guess it depends on what you're happy with clearly you want something able to be registered and reliable. At least you'll know how to fix it if something goes wrong!!
Yeah with the pitbikes i do love them I would trust a linkage bike with all new fasteners etc for a long ride but would want to go over it with loctite..

will see how long the new (ish) psto 125 goes for as a stocker at the farm.. So far all its needed is a brake bleed

the race bike is still sitting there because if i put another grand into it it goes to dead weight.. one day when i have the spare cash i may feel like splashing it
Atm its "for sale" because i wouldnt feel bad about the money to complete this bike but i dont want to miss out on this good community that i have seemed to hang around for ages with but only ride a few times :p had a blast though

Maybe if my next jobs a bit better in pay (just quit the previous) i will be able to finish the wr and the pitty and have the best of both worlds..

Imo rec reg isn't worth the $100 cheaper difference if you work it out with insurance + if your "accidentally on the wrong trail/road" etc.. etc..

The next big problem is fighting the decent amount of heat (and getting the next job) the 450 produces in single trails.. Maybe some small high speed computer fans with a nice custom bracket may be in order..

Wouldn't mind a track bike one day but i should have almost all the fun i desire on the wr at the track unless i really get into it
 
Mate, I think rebuilding the bike and knowing what makes your bike tick is half of the satisfaction in motorcycling.

Sucks about the crank though. Loving this thread.
I don't think much of the crank actually, even though it looks a little chewed up nothing about it is unusable (accept of cause the rod) so i may just run it unless i get the extra $200 and buy a whole new assembly

But that + the other nice options i will be taking will take more and more time and $$ + approx 1k for rego dont want to loose too much if its still usable..

Mate, I think rebuilding the bike and knowing what makes your bike tick is half of the satisfaction in motorcycling.
Isnt that true.. especially with bikes of today its coming to a point (if you want performance) you have to have the dosh to keep one (or own it while its in very safe bottom end service life) Or learn to pull it apart to rebuild them Its not like the days of the xr 600's where they go and go and go (even so alot of those bikes are getting long in the teeth) Unless of course you want a drz or a klr but there prices are holding kind of well and if you get a lemon you stand to loose alot..
 
Isnt that true.. especially with bikes of today its coming to a point (if you want performance) you have to have the dosh to keep one (or own it while its in very safe bottom end service life) Or learn to pull it apart to rebuild them Its not like the days of the xr 600's where they go and go and go (even so alot of those bikes are getting long in the teeth) Unless of course you want a drz or a klr but there prices are holding kind of well and if you get a lemon you stand to loose alot..

I must admit I do enjoy working on bikes, gets a bit annoying at times when nothing fits or goes right but you get that(good for patience too).

Its really funny you mention old xr 600s I had a mate that bought one second hand from a shop years ago, thing was a ***** to start, he could hardly even kick it. Had some serious problems with spark or something, didnt know much about motors back then except he bought a dud bike and had bugger all idea what was wrong with it....or how to fix it!! Damn it went fast the couple of times I saw it running though....
 
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She is starting to resemble a bike..
Funds are finally starting to look up a bit.. So test jigging everything up.. need to print off some diagrams etc and measure and find where every bolt lives and purchase new ones if required.

I also have a different paintjob i would like to give the frame.. this will be my 1st proper paint job diy of course.. It will probably be black unless i get another idea/inspiration.

1k + a bit is what its going to cost to get the motor in almost tip top shape +all bearings.
And then the tank and seat combo along with the front fenders.. + 500? going to go the clear ims tank i think.

The wheels are a little buckled but i am not worried about them just yet and should be okay to pass a roady if i do get it rego'd.

Front forks have quite a bit of wear on the chrome i will see if i can polish it out.. and replace the seals and talk to a suspension shop as i do for the parts and advice.

Before
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After a little love
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It seems i will have spent approx 3k all up + a bit for rego if all goes well..
Thats a little over the market value however i will know i can jump on today and go compete in enduro events all over australia and be 75% less likely to run into major problems.
More importantly i will not owe money to nobody unlike if i was to buy a new bike and pay it off.
 

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This one is a little too black for my liking.. Wouldnt mind looking into the 2005 plastics swap though :D
 
Nice work mate, slowly coming together, that black looks nice I think, its like a satin black or something, I bet your dying inside to get it finished and ride it, lol. Ill get some pics of mine asap and post them up.
 
Nice work mate, slowly coming together, that black looks nice I think, its like a satin black or something, I bet your dying inside to get it finished and ride it, lol. Ill get some pics of mine asap and post them up.
Lol like you have no idea :p
Would love to see that gas gas pics.. along with it in action :p

Okay im almost sold on the 2003 wr 450 plastics conversion..
Looks like im in the market for a rear subframe, full plastics kit and airbox.. along with tank.
I would love to install a 26 litre safari tank however it will not fit the 2002 frame because of the dip stick..
Will look into it some more.. and see if i can re-locate the dipstick to the 03 after rego ofcourse or relocate my adr plate onto a 2003 frame *Nope that could end bad

Not sure if i could re-mould the plastic a bit by heating it and shaping it...

Any way i will focus on the engine for now but keep the 2005 plastics in my mind as because it may be cheaper than purchasing a new clark tank for my 426 + seat +shrouds... Already emailed a bloke in QLD

Still need to add some smaller things to my list of parts like clips and washers etc then get the order in and get the bugger assembled after getting the gears back cut.

On the paint im thinking of doing a textured black? i cant explain it i may just have a look in a paint store for a little while and pick one that feels good.. I want something that hides scratches (as its going to be used in dirty conditions) but still looks pretty mint..
Thinking a satin black with a clearcoat of speckils or whatever you call them..

Cant think of another colour that would suit it with the blue fenders... id love a deep orange/black combination but thats too much like a ktm lol.. dont think it would sit too well with the blue fenders..

deep purple?.. nah too much like the 80's bikes

White could look mint... for 5 seconds.

could go a hot red though.. not sure..
 
you could use VHT Black Wrinkle finish for this look
you need to play around with times between coats, and spray the last wet coat pretty wet
it is heat proof too

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