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Discussion Starter #1 (Edited)
Over the weekend I picked up a non-running F4. The previous owner was driving on the highway when he heard a "whirring" noise and the motor died. He had it towed to a shop, which pulled the airbox off and saw two bent valves. Not knowing what else might be wrong, they quoted the PO $3-8k for repair. :jsm: I've seen this failure before, and because valves are so thin and weak it's unusual for damage to be too widespread.

I bought it for $1800. The reason for the low price is that it's not an exceptionally clean bike.
The Bad
-Carbon Fiber aftermarket fairings. It came with a full set of CF fairings but no OEM fairings. The condition of them is fairly nice, maybe 7/10. It's missing the small trim pieces that go underneath the tank.
-Has stock Arrow exhaust, but baffles are removed. So it's going to be loud as heck.
-Rear fender is gone and replaced with some crummy folded aluminum to serve as a fender eliminator. One rear turn signal is missing. That whole section needs to be redone, either with an aftermarket fender eliminator kit or with used OEM parts.
-Aftermarket brake/clutch levers and aftermarket rearset
-The aluminum engine covers are somewhat tarnished from previously living outside at one point. I'm researching methods to bring back the shine on these parts. Suggestions welcome!

The Good
It was $1800, and repair parts have been ordered already totaling $263.

The teardown went smoothly and was finished after about a full day of work. I separated the frame into two pieces as previous forum members have done, which worked well. I took lots of photos to document the process and help me remember how it went back together! The only problem I ran into was removing one tight cam keeper bolt, which required propane torch heating, a Snap-On hex bit, and hammering. In the end, the problem turned out to be 2 sheared screws holding the intake camshaft sprocket onto the camshaft. I've seen threads about this happening to other owners, too.
 

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I must say you're the first person I ever heard complain of aftermarket rearsets and those look like sato sets which are pretty pricey I know cuz I have them on my bike :stickpoke...half of the bad things you listed are actually good things in my book I mean a loud exhaust to most is a plus and so are aftermarket levers but the topper is complaining about carbon fairings:jsm::jsm: Those aren't cheap neither especially if you give them a 7/10 if you don't like em you can sell em and get the fairings you want you got a bargain and good luck with the build and welcome to the forum
 

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Exactly my first observation is the complain about goodies which are top dollars.
I see even a CF air box.
In case You don't want the CF fairings send me a PM.
Rear sets we can talk about than either as the after market levers.
 

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Discussion Starter #4
Hey guys, I'm thrilled to hear that these aftermarket upgrades are desireable! For whatever reason I expected bikes modified away from stock to be significantly less valuable.

Cosmetically, I'll probably keep the bike as-is. Reinstall the carbon fiber fairings because they look pretty decent.
 

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Discussion Starter #6
Tonight's progress included successfully removing the sheared cam sprocket screws and removing intake valves.

I used a 6" hex extension and a 3/32" hex drill bit to pre-drill the center of the first screw. Then I hammered an easy-out into the screw and backed it out. The second screw turned by itself when I started to drill it out.

I used a C-clamp with a small custom end-effector to remove the valve keepers from the valve stems. I removed all 8 intake valves and found that 4 were bent in all. Luckily I bought an 8-piece set of eBay. The seals also seems worn out so I will need to replace those too.

Overall the head looks undamaged. The combustion chambers are covered in a thin layer of grime which will all be cleaned up manually before it goes back on. I have a lot of scrubbing to do!
 

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Discussion Starter #7
Tonight's work was primarily cleaning. After removing all the exhaust valves, I thoroughly scrubbed the entire cylinder head, pistons, and cylinder sealing surface. Wow, the pistons really cleaned up nice!! Their CNC'd surface shines as bright as the day it rolled off the assembly line. Cylinder walls look healthy too. No obvious scoring and cross-hatching is visible on every bore. I coated the walls with a thin layer of oil to help keep the pistons lubricated through any manual cranking.

I also re-lapped the exhaust valve seats with lapping compound. I'm waiting to lap the intake valves because the replacements haven't arrived yet.

Finally I removed the valve seals using needle-nose Vise Grips. (sorry, no photo)
 

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Very nice account of the strip down, keep up the good work and looking forward to seeing the finished bike, good luck
 

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Sounds like you'll have that beast up and running in no time.
You have probably made the steal of the century with the price for that bike.
 

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your project bike

Andrew, I have a complete set of factory OEM skins and hardware for your F4, if you need it. Back in 2009, I purchased the complete set that was an extra for the movie, Batman. The carton has been sitting in my warehouse for all these years, and Im looking to sell it, gas tank, seat post, side panels, all of it.
 

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Welcome

Andrew, I have a complete set of factory OEM skins and hardware for your F4, if you need it. Back in 2009, I purchased the complete set that was an extra for the movie, Batman. The carton has been sitting in my warehouse for all these years, and Im looking to sell it, gas tank, seat post, side panels, all of it.
Take some pictures and stick me into the For Sale section mate.
 

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Discussion Starter #15
Hi all,

Been a while since much work's gotten done; I've been intentionally paused waiting for parts! Ugh, parts were ordered 3/31 from ProItalia and will arrive tomorrow 4/29. Darn near a month later... Next time I'll definitely hunt harder domestically before just going to a dealership.

Since the last update, I completely disassembled the head and installed new intake valves. The new valves have a slightly different shape than the originals for unknown reasons. They're also about 0.8mm shorter than the originals, requiring all new shims. (exhaust valve gaps were mostly in spec). I lapped both intake/exhaust with valve grinding compound from the local auto parts store.

I've attached some photos from the disassembly/reassembly. The spring compressor tool is a simple steel tool I made years ago for a CBR600 and has come in handy a surprising number of times. For removing buckets I like to use a shop magnet, and they pull right out. For those of you following my valve seal purchase debacle, here's a side view of the valve guide.

Finally, the new head gasket arrives tomorrow! At that point reassembly will commence. I have a busy weekend coming up so hopefully she'll run early next week! :mouthwate
 

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nice work. I'd be a bit concerned why the replacement (intake) valves were that far off. Are they dissimilar weights too compared to the old valves?
 

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Discussion Starter #18
Fired up the F4 today and it runs great! I'm very impressed with the smooth throttle response, thanks to the fuel injection. Runs much more smoothly than my carbureted CBR 600.

Clayp, the replacement intake valves are most certainly a different part number than the originals. I can't explain why or how. But I replaced all 8, hoping to negate the difference in mass. I have a hard time believing a different mass of intake valves vs, exhaust valves would make the machine not run well.

hb88xx, the chemical that really did the trick was O-Reilly's brand "foaming engine degreaser." It was cheap, readily available, and really worked well. It worked its magic most effectively on cast aluminum engine parts and the exhaust.
 

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Originally Posted by AndrewB View Post
-The aluminum engine covers are somewhat tarnished from previously living outside at one point. I'm researching methods to bring back the shine on these parts. Suggestions welcome!

Mine are just mirror polished(not easy to see in the pics though), a bit of upkeep yes, but not that much with the right product start with this, see link http://www.briliant.biz/products/Aluminium-Polish-.html and then a polish with a sealant wax in it, see link http://www.briliant.biz/products/Metal-Polish-And-Sealant.html
Excellent products, easy to use. If the surface was very poor to begin with I may use an abrasive paste like Autosol first. See pics http://www.mvagusta.net/forum/showthread.php?t=36930&page=45 "post 447"
 
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