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I Think it's rebuild O'Clock


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Skyntara

 
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I Think it's rebuild O'Clock

Tue Aug 18, 2009 8:36 am » Post: #1 » Download Post

Hi Guys,

So the rough idling is the least of my worries now. I took the exhausts off and checked out my pistons.

Not pretty

FRONT:



TOP:



If you check out the whole set at the link below:

http://pictures.1337it.com/index.php?directory=Pistons

You will see the exhaust is blowing past the rings but there doesn't seem to be any marks on the lower parts of the pistons.

The front piston shows some marks whereas the top appears the be blackened but maybe not worn.

I'm hoping this is just regular wear and all I need is a top end rebuild - please advise.

I haven't popped the cylinders off yet as I think it might be worth pressure testing the crank case before I do. Is this a good idea?

Look forward to advice.

Clancy (now a carbon member :)
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StephenRC45
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Tue Aug 18, 2009 9:06 am » Post: #2 » Download Post

Top picture is a seizure. That needs to be replaced and have a good look over the bore.

Second picture looking like foreign object damage and is also not normal and needs to be inspected.
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Skyntara

 
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Tue Aug 18, 2009 9:10 am » Post: #3 » Download Post

Is the exhaust marking down the sides ok or is that a bad thing too?

Also, should I attempt a pressure test before I pull the barrels off or not bother?
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StephenRC45
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Tue Aug 18, 2009 10:14 am » Post: #4 » Download Post

The marks down the side are where it's seized.
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Skyntara

 
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Tue Aug 18, 2009 11:13 am » Post: #5 » Download Post

Ok,

So I'll order a couple of top end kits from Tyga (C cylinders)

I don't have any jets other than what are in the carbs - should I order some more in various sizes?

Do tyga stock jets, I see HRC ones but no normal ones.

Sorry if this is too "jetty" for general discussion.

Should I order some spare gaskets or not bother?

Does Tyga give any love to supporting members? I have a full Tyga exhaust and some tyga fairings on the bike if it helps any.
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StephenRC45
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Tue Aug 18, 2009 11:24 am » Post: #6 » Download Post

You need to get the cylinders off first and make sure they will go again.

No point ordering pistons for a cylinder you might not use.

Yes tyga will sell all you need.

HRC jets are the same jets as stock but in different sizes.
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Matt@TYGA
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Tue Aug 18, 2009 12:28 pm » Post: #7 » Download Post

The pictures are not that clear, but it looks to me like you'll be wanting to clean up those exhaust ports a bit. All that goo can't be a good thing.

An afternoon spent cleaning will make a noticeable difference.
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Skyntara

 
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Tue Aug 18, 2009 1:51 pm » Post: #8 » Download Post

Alrighty,

Front Cylinder and piston are off the bike. Based on what I could see through the exhaust port, this was the worse piston of the two.

Piston is barely marked, barrel still has nice crosshatching with only a little metal from the piston on the exhaust side.

I will post some pics when i get the top cylinder off.

I'm having trouble with one nut on the top cylinder. You guys probably know which one it is.

The one at the front right, under the PV assembly and behind the water hose connector.

Can't get a good lock onto it with a spanner - the spanner butts up against the cylinder. Can't get the ring spanner around it because it won't fit. Can't get a socket onto it. What's the go there?

All I can think of is dremelling down a spanner so that it will fit.

Also, I may have found the cause of the seizure. I have been foolishly running motul 800 in the pump. I'm guess that would cause a lightish seizure after a few hundred Ks.

I'm kicking myself for running 800 on the pump and also for not checking the pistons earlier - I have sprung race pipes for God's sakes.

Anyway, I can't order the rebuild kits until I get that second barrel off since Honda, in their infinite wisdom seem to have put the designation stamp behind the 1cm x 1cm hump in the crank case that has a tube running off it. What the hell is that?

Thanks again for the help guys, suggestions on that last nut that don't involve a sledge hammer or a long jetty would be great.
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cgallant
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Tue Aug 18, 2009 3:01 pm » Post: #9 » Download Post

for that nut, you should be able to use an open ended wrench. Shouldn't have that much torque on it that you can't get it off... Maybe spray a little liquid wrench/WD40 on it let it sit over night and see if that might help make it easier.

For torquing that nut back down, I use a crowfoot wrench (they fit on a rachet wrench).
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Kubira

 
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Tue Aug 18, 2009 4:17 pm » Post: #10 » Download Post

Ive just removed my barrels too, hadda go buy a 12 mm ring/open end ( i was sure i had 3 or 4 Confused ), only needed it for 1 of the 4 nuts on each barrel tho, no grinding of the spanner either, fit and turned no dramas
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Matt@TYGA
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Wed Aug 19, 2009 3:36 am » Post: #11 » Download Post

cgallant wrote:for that nut, you should be able to use an open ended wrench. Shouldn't have that much torque on it that you can't get it off...


I have to say that this is a dangerous game to play. Thos nuts can be pretty tight if a cowboy's been in there before you.

Just grind yourself a dedicated 12mm ring spanner (wrench). That's what I use.

As for a crowfoot fitting for tightening up, good advice. Never got around to it myself, so welded a 12mm nut onto the (ground down to fit) 12mm spanner. Perfect.
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Skyntara

 
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Wed Aug 19, 2009 8:35 am » Post: #12 » Download Post

OK, Barrels are off, pistons are out!

That last nut was a bugger. I ended up grinding down a ring spanner. The open ended one was doing more harm than good, it had to be a ring spanner.

Pistons look messy, but not too bad. Barrels actually look not too bad to my untrained eye.

Mad pics below - I wish I had something shorter than a 100mm macro lens.

Piston 1:



Piston 2:



Barrel 1:



Barrel 2:



The dust you see in the barrels is just a bit of fluff from the rag - there's no pitting or scratching or anything, just a bit of light marking from the pistons. Crosshatching is good on the front cylinder and fair to good on the top. Barrels are mismatched - B on the top, C on the bottom.

Rest of pics below - shots of all parts from all angles.

http://pictures.1337it.com/index.php?directory=Pistons&currentPic=11

So I'm ready to pull the trigger on a C and a B rebuild kit. Please tell me the barrels are ok.

Will I need anything else?

I'm calling this a lightish seizure and assuming it was from my choice of oil and hopefully not something more sinister, let me know if you concur.
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Andy
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Wed Aug 19, 2009 12:37 pm » Post: #13 » Download Post

Fontyyy would race with those pistons! Laughing
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Skyntara

 
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Wed Aug 19, 2009 12:39 pm » Post: #14 » Download Post

Not sure if that's serious or not.

I'm hoping it means it's not too bad.

Just whack some new pistons in and oil her properly this time?

Tyga don't seem to have a B rebuild kit in stock. What to do, what to do.
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Andy
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Wed Aug 19, 2009 12:42 pm » Post: #15 » Download Post

Well just order 2x piston kits and make a note on your order so that Matt or Paul can either pick the correct parts, or contact you with options.

I've seen barrels infinitely worse than those re-used.
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