Engine out, what else should I do?

[surfish95747]

Okay guys, winter is nearly upon us here in Utah. I will soon be removing my engine (once the ice and snow stars sticking) and want to see what else I should do to the engine while it is out. I will already be putting new piston rings on, and honing the cylinder walls. I will be adjusting the valves (should I do new valve seals/springs?) and checking on a leak over by the oil pump. Besides a really good cleaning, any other routine maintenance I should do? Thanks!

[shinyribs]

Since the bike still be light and manageable, check the swing arm pivot area for any slack. Also the steering bearings and forks.

-Engine
-Rear suspension
-Front suspension

Geez, that's pretty much all there is. :p

[surfish95747]

Thanks man! Yeah I'll be putting on a Yamaha R1 front end and a cbr rear wheel (making it the dreaded Oreo, but I like oreos soo) on this winter too so I will definitely be checking those too. I forgot and left that off my OP. You guys ever use Vesrah gasket kits? I've seen mixed reviews about them.

[Truck]

Since your doing rings and a hone, may be a good time for a big bore kit....  

[surfish95747]

Dang it Truck, I want to! We'll see what my budget is like. Rules?

[surfish95747]

I've been lookingat the Wiseco 823cc (I think that's it) kit that Cycle X sells.

[shinyribs]

More power is fun, but so is not being broke.  Go ahead and build your bike now ( suspension,brakes,etc) and just pick up another set of jugs to borw when your budget allows.

If you're just doing a ring & hone job, that's ^^^ what I'd do. But if you end up discovering that you need pistons and rebores anyway, well....no reason not to go big.

[surfish95747]

Words of wisdom. Thanks shinyribs. We'll see what I can work out.

[TOOLS1]

Doesn't cruzinimage on ebay have kits for the DOHC engine?
TOOLS

[surfish95747]

I'm not seeing him as a seller on eBay. Can you find him on eBay?

[surfish95747]

What might be your guys thoughts on this kit. From Australia?

http://www.ebay.com/itm/HONDA-CB750-K-DOHC-79-82-820cc-BIG-BORE-KIT-65mm-PISTON-RINGS-GASKET-/131255269244?hash=item1e8f6c777c:g:wg0AAOSw7NNT2ILT

For $250, that doesn't sound too bad.

[TOOLS1]

Here you go. http://www.ebay.com/itm/79-82-HONDA-CB750F-FZ-FA-FB-823cc-BIGBORE-PISTON-KITS-CB750FBB-/141196522368?hash=item20dff7f380:g:OAwAAOxyfS1R3TjD&vxp=mtr
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[surfish95747]

Thanks tools. So, why is this so much cheaper than a Wiseco kit? Name brand? It makes me nervous not spending enough money on something like this, but if I don't have to I don't want to. Do you guys have any experience with these? I read a little bit about the Australian big bore kit and sounded like there was a little that had to be done to these pistons but that they worked. Thanks guys!

[surfish95747]

Oh I also forgot to mention in my OP that I will be putting in some cams from a CB900F. ;)

[TOOLS1]

I have use three of the 836cc kits from that seller, and some kits for other engines, and not had any problems. Also, Red from Cycle-One has done several of these, and speaks very favorably of these kits.
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[surfish95747]

Thank you very much! That will save me some cash! Now I guess I can do the big bore kit. What is the difference between these kits and the Wiseco kits?

[surfish95747]

Do you think this kit will also be the same kit I would use for a cb750K, seeing as how this kit is listed for a cb750F? Thanks man!

[shinyribs]

surfish95747 wrote

Thank you very much! That will save me some cash! Now I guess I can do the big bore kit. What is the difference between these kits and the Wiseco kits?

My '80 has Wiseco's in it. I think there may be different pistons available, but most of them are high compression. My jugs have a spacer under them to drop the compression so it will tolerate pump gas. Jug spacer also means custom length cam chain. Just added cost/fiddling that a street bike really doesn't need at all.  But mainly, yep, you're paying for the name/reputation.

I'd have no fear going with the ebay pistons. When they come in, if you see a hunch of sharp edges, just smooth them over with some 600 grit and rock on.

You'll be surprised how well a 823 with 900 cams runs. With stock gearing on 17'' tires I can hit 100mph in 3rd with ease.Once 3rd gear hits about 120 I back off. Never tried to go any faster.  It won't rev and charge at upper rpm's like a modern sport bike will, but it will have torque down low that the new sport bikes aren't making at the same rpms/ cc's.

A stock 900F only had 8.8:1 compression. At 901 cc's it made an honest 95hp through stock exhaust. An 823 with decent compression, good exhaust and properly tuned carbs (stock jetting is horribly lean) will make that same power. Work on the head and you can make even more. I gave a early 00's ZX750 a run for his money one day. He was shocked I could hang with him...so was I!   Those bikes are about 20lbs lighter and spec'd around 120hp. Not to mention their aero advantages. When you keep the original torque and add hp it makes for a great running street engine.

Hey, while you are thinking about all this look into 900 rods. Much beefier pieces. With good valve springs they will allow you to turn the bike up past 10k rpm with confidence. I've taken mine to 12k many'a times. You might be able to get some 900 rods cheap off ebay.

[TOOLS1]

surfish95747 wrote

Do you think this kit will also be the same kit I would use for a cb750K, seeing as how this kit is listed for a cb750F? Thanks man!

With the DOHC engines, there is NO difference in the engines between models.
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[Truck]

I see a Big Bore race coming!!!!