I was just wondering if there is any way to get more rpms out of a stock ct70?... well stock all except the carburator, air filter and valve springs. I installed the heavy duty valve springs when I put a race cam in. I have taken the race cam out and put the stock cam back in. I also have replaced the stock carb with a pz19 carb. I ground out the intake manifold about two millimeters in diameter on the carburator end so the inside diameter would be closer to that of the after market carb. Is there anything I can do to allow the the bike to rev higher? With the stiffer springs I don't think I have to worry about floating the valves or over reving it.

Also, this has nothing to do with rpms, but I did a compression test the other day and is was able to max out at 170-180 psi. How good of compression is this for that engine?

I'm getting someone to rebuild the engine on my CT70HK1 with a Mitsubishi stator. On all the parts diagrams I can find it looks like there should be a nut and washer on the end of the crankshaft to hold the stator on. On the one I have it bolts on instead. Could this possibly be the wrong crankshaft? Does anybody know the correct part number for the bolt if it does bolt on? I would like to try to keep this engine as close to original as possible, so any help would be appreciated. I hope my question makes a little sense because I'm not a mechanic, hence the reason I'm getting someone to rebuild the engine for me.

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I have two 1972 CT70 K1's and one bikes exhaust note is overall mellow and relatively quiet.

The other bikes exhaust note particularly when accelerating has a MUCH louder (excuse the reference) wet farty and raspy sound which to me is irritating!

They both seem to have the same stock exhaust, both with the baffles installed.

Does the tune of the engine have any bearing on the very different exhaust note between the two? Why the big difference? :39:


...Glenn :)

So I have my CT70 all apart now awaiting rebuild and just curious if my bike is what I think it is. The bike has 1699 mi on it and its vin # is 197288. The plate on frame neck says manufactured in 7/70. From what I remember my uncle bought the bike new and sold it to my dad in in the early 70's. Dad is turning over the pink to me and I am rebuilding for my 8 yr old daughter to ride. So I believe it is a 1970 Honda CT70 KO model, correct?

On a side note where is the engine serial number located?

I am new to the CT 70 world so please excuse my ignorance but wanting to get educated before I get too deep into this fun little project bike I have. Long story but I picked up this CT 70 and I'm stumped and confused about what model it really is. Paid very little for it as is ( Wouldn't start ) but want to determine what year - model before I purchase any possibly wrong parts in my efforts to repair and restore it. The title ( Yes, it had a clean title and was previously licensed for street and off road use plus it looked pretty good overall which is why I "Went for it" ) states it is a 1970... the DOM on the tag on the front fork is 1/71
and the VIN # on that tag, on the title, and on the frame is CT70-246XXX. The engine serial # is CT70E-246XXX. ( 6 digits, not 7 ) and it has KO color, decals, and parts - like a plastic tank, all chrome exhaust shield, etc. But is the VIN # right for a 70? A guy at Honda America told me it is a 75! Thanks for the help.

Well I live in Stillwater Oklahoma and wanted a good OSU tail gating CT70 so I don't have to park a mile from the stadium. I finally got my powder coating process streamlined so I decided to start on this project today.
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I have my entire 1970 CT70 taken apart but I can not figure out how to get the fork set apart from the frame. I got the large nut off the steering head but can not get the fork apart. What gives?

I just purchased my first CT70 (last friday) it has been sitting in a barn for many, many years. It is a 1971 and the kick start is very easy to push down and it DOES NOT turn the fly wheel. It only has 753 miles if that matters. I'm not the best wrencher in the world and I have never rebuilt an engine, but i'm going to make this one happen. Someone stear me in the right direction on my new little friend!!

I was told that an SL70 flywheel with the auto advance would not fit a CT70 flywheel. Different tappers on the crankshafts.

Well I placed both an SL70 and CT70 flywheels on the same SL70 crankshaft. The both seem to fit properly.

I can see no difference in the tapers on a CT70 and SL70 crankshaft.

Comments please.