.
Yeah sounds fun but your post makes no sense to me . . You have a 200 cc engine that spins to 9,000 rpm but it has trouble going 60 mph . . The math just doesn't add up unless you changed the gearing, and if the rods and pistons are stock, it might hurl if you try to spin it a lot higher.
CAMS
Look at page 20 under your model in the link below and you will see two different cams, however, they make several more that they don't list . . If you run stock compression, I would NOT get the bigger cam because it will be a pig everywhere, however, if you run at least 10.5:1, i would run a bigger cam . . the first cam they list is very good for tight corners but not great for top end, and since you will be at wot or close to it all the time, you are better off with a cam that is designed more specifically for that app, UNLESS, yo ride the bike on the street also, in which case, you want a cam that is more inbetween.
They use your cam and the cost is $310.00 . . If your cam bearing journals are worn, ask them if they can fix those also.
http://www.megacyclecams.com/catalog/catalog_optimized.pdf
Here's one of the cams they don't show online.
P/N 135x10 ... lift 288 . . dur @ .020" 276 . . @ .040" 251 . . lsa 105
PISTONS AND COMPRESSION VS CAMS
Compression is your friend . . This is an area that is frequently overlooked by almost everyone from what I have seen, and it is a fairly complicated one, so I will make it as simple as I can . . In general, the more compression an engine has, the more power it will have EVERYWHERE, therefore, you should ALWAYS run as much compression as you can for the octane gas you are using.
In general, the bigger the cam, the LOWER the compression will be . . This is caused by the valve timing . . If you put a big cam in low compression engine, it will be a P I G, especially in the lower rpm range.
The lighter the pistons are, the faster and farther it will rev if all else remains the same.
In your case, you can have around 10.5:1 compression if you run their street cam using 93 octane or higher . . If you use race gas or E85, I would go to 11.5:1.
If you run their race cam, you can go to 11.0:1 with 93 and 12.0:1 with race gas or probably 12.5:1 with E85.
RINGS - Ask them if they can make the rings thinner than stock with a plasma coated top ring and napier or reverse twist second ring . . This will reduce friction which will increase rpm and reduce heat.
PISTON PIN - Ask if they can make a tapered ones . . This will be lighter
PISTON WEIGHT - Have them make it shorter and lighter than stock.
PISTON COATING - Ask it they can put a coating on it . . This will reduce friction.
ARIAS can make forged pistons in 4032 or 2618 material for only $200.00 each . . The minimum is 2 pistons . . it will take 4 weeks.
http://www.ariaspistons.com/contact.asp
PISTON TO CYLINDER HEIGHT
The outer edge of the pistons should come perfectly even with the top of the cylinder but often they don't because of production tolerances . . If you have pistons made, measure the distance from the top of the piston to the top of the cylinder and give that to them and they will lower the piston in that amount for no extra charge.
VALVE SPRINGS
R&D brand p/n 252H from Megacycle if you run any cam bigger than their street one . . You can also run these with their street cam for added insurance if you want . . They come with titanium retainers . . $250.00.
ROCKER ARMS
You should have them hard weld your arms if you run the valve spring kit . . Also, unless yours look like new, you need new ones or hard welded ones anyway because the old ones will quickly damage your new cam . . $75.00 each
CAMSHAFT OILING
These have a weak oiling system to the cam especially on the left [points] side, and it is my belief that damage caused to both bearings is due to the use of cheap oil or oil with low levels of ZDDP and/or infrequent oil changes and a delay in oil to the cam caused by oil draining back into the pump after the engine is turned off.
There are several mods to reduce this problem . . one is to use 175 cam holders and add an oiling hole to the case and o ring around the bolt.
CYLINDER HEAD
Get a mild port job/blend on your cylinder head and send the intake boots with it . . It needs a LOT of MINOR work in several areas, but does not need a full blown 5 axis CNC type job . . The exhaust has a bulge in it that can be reduced a little to open the port some which will help a lot but it doesn't need much . . The intake tract has some irregularities which should be smoothed, and the area around the valve guides and the guides themselves can made smaller with an improved shape . . The area where the bottom of the valve seat meets the head often has a small lip which can be smoothed and the seats can have a 3 to 5 angle cut and the intake valve can be be "back cut".
CAM CHAIN
Racing chain or DID brand.
EXHAUST
Get decent exhaust if yours is stock . . If the exhaust is not made incorrectly, it will not rev as much as it should . . I have seen a modified 200 rev to 11,000 rpm sing stock CL175 pipes and no muffler.
CARBURETORS
Standard Mikuni carbs are common . . 22 mm should do for your app, but I would run carbs with an accelerator pump if you also run it on the street . . You will likely need bigger intake boots for the 22 mm carbs but measure he inside of your boot.
I would be tempted to find some used cb160 carbs because they are 22 mm and also see if the intake boots fit . . The Honda carbs use a different needle jet and will be easier for you to tune.
The 175 had 20 mm carbs which are still better than what you have.
CARBURETOR ADAPTER
If I have this right, the inside of the carburetor adapter is slightly bigger than a 20 mm carb, which means you can put 22 mm carbs on it, and at the worst case, you would need to enlarge the hole in that end of the boot just a little.
I think the intake port in the head is slightly larger than 20 mm, so this would not need to be enlarged to use 22's, however, there is often a slight mismatch between the carb boot and the head, so if the head blocks any on the the hole in the boot, see if slotting the holes in the boot allows you to move it enough so you can no longer see the face of the port in the head with the boot on it . . If part of the port in the head still blocks the hole in the boot, the entrance of the port in the head should be ground to match the boot.
CAM GEAR
Get an adjustable one for fine tuning.
P/N 150 or 155 . . email to find out what the difference is.
http://www.cappellinimoto.it/index.php?option=com_djcatalog2&view=itemstable&cid=4&Itemid=11&lang=en
IGNITION TIMING
Match the ignition curve to the engine.
SPARK PLUG
Run a spark plug that is 1 step colder than stock.
ENGINE OIL
High quality shear free high zinc synthetic 10w-30 or 10w-40 or 5w-40 engine oil.
Here's two options.
http://www.penriteoil.com.au/products.php?id_categ=7&id_subcateg=95&id_products=599
http://www.penriteoil.com.au/products.php?id_categ=7&id_subcateg=95&id_products=597
OIL COOLER
Get one.
GEAR RATIO, RPM, MPH
If your gearing is 15-35 and you have a 3.00x18 tire that is 24.5" tall, your speed in 5th gear at 9,000 rpm has to be 75 mph . . If you build it so it will rev to 10,000 rpm in 1st gear, it will rev to around 9500 in 5th gear which would be 79.5 mph.
If you go with the race cam instead of the street cam, you can just put a 1 tooth smaller counter shaft sprocket on it for around town and it will have decent bottom end power again.
http://www.wallaceracing.com/gear-speed.php
WEIGHT REDUCTION
RIMS -Aluminum.
CHAIN & SPROCKETS - Possibly an aluminum rear if you need to change it anyway, otherwise, switch to a lightweight 428 size set . . No, it will not break.
FENDERS - Fiberglass or plastic etc.
KICK STARTER - Try to find an aluminum one that will fit.
STARTER MOTOR - Remove it and buy the plug below to cap off the hole . . P/N 163 . . Also remove the starter chain, the starter gear and the one way clutch on the back of the stator . . This will not only remove maybe 10 lbs, it will also increase the engines performance by removing rotating mass from the crankshaft.
http://www.cappellinimoto.it/index.php?option=com_djcatalog2&view=itemstable&cid=4&Itemid=11&lang=en
ALUMINUM RIMS ..................... - 5 lbs ?
ALUMINUM KICKSTARTER ......... - 2 lbs ?
LIGHTER FENDERS ................... - 4 lbs ?
LIGHTER DRIVE CHAIN ............. - 2 lbs ?
REMOVE STARTER ASSY .......... - 10 lbs ?
TOTAL ................................... - 23 lbs ?
OIL COOLER & ADDITIONAL OIL .+ 2 lbs
FORK BRACE ........................... + 1 lbs ?
MINI FAIRING ........................ + 3 lbs ?
TOTAL ...................................... 16 lbs of weight removed
TIRES
If you are not pushing hard in turns and curves, the skinnier and the stiffer the better with air pressure on the high end . . You will easily gain a couple mph with the right tires and high air pressure.
STABILITY
Going 80 is a LOT different than going 60, so I would run a fork brace and stiff suspension and possibly lower the rear a little if there aren't many low speed areas.
MINI FAIRING
This will increase your top speed by a couple mph and will keep your hair looking nice too!
https://www.google.com/search?q=honda+cb200+cafe+fairing+images&biw=1093&bih=506&tbm=isch&tbo=u&source=univ&sa=X&ved=0ahUKEwjkvd6uk-zJAhXGbj4KHXqLDd0QsAQIGw#imgrc=OG8jBUq5wc-RHM%3A
EXPECTED PERFORMANCE
You should hit at least 80 mph with the above setup if you use one of a race version of Megacyclesa cams. .
CAM CHAIN ROLLER
The roller in the bottom of the photo takes a beating and can be replaced with a metal one for around $100.00
P/N 154
http://www.cappellinimoto.it/index.php?option=com_djcatalog2&view=itemstable&cid=4&Itemid=11&lang=en
