When starting a CT-90 or CT-110, you should know a couple of things.

First, this is a carbureted engine, and second, it has an automatic clutch. Most well-maintained CTs are quite easy to start. My 110 often starts on the first or second kick after being stored without fuel all winter. My old 1970 CT-90 was so gentle it could be started with your hand. However, some CTs can require a little more effort.

First, the choke. The “up” position (lever pointing toward the back of the bike on the 1969-on machines) is “choked.” Flip it up. Make sure the “altitude compensator” is not pulled out if the bike is equipped with it. You may not need the choke at all on a day where the air is 75 degrees or higher.

Turn the ignition on. You should see a green neutral light on the speedometer face. If not, step on the front of the gear lever until you get to neutral. Remember that the green light might be burned out. CTs can be started without a good battery, but it’ll be harder than if the battery has a good charge. If you can’t beep the horn with the key on, consider charging the battery.

If you’re on the bike, take it off the stand (center or side). Push the kick start down slowly a couple of times to charge up the fuel/air mix and to build up a little compression. Then, kick sharply. If the bike tries to push forward, kick it down in neutral (for real this time).

If you’re next to the bike, stand to the right side and kick it from the right side. You can, if you want, kick it with your left foot. Sometimes this is a good way to get a bruise when your foot slips off the kick starter.

If the bike starts, take it easy, and don’t try to rev it right up. Let it warm up a little bit and get some oil into the head.

Once it has warmed up enough, drop the choke lever back down and let the bike breathe. At this time, you can run the RPMs up a little. If it stumbles or sounds like it’s struggling, put the choke halfway back on.

Driving the Motorcycle

Remember, this is an automatic clutch, but it is not an automatic transmission. You have to shift it. • Push on the back part of the gear lever. This should put you in 1st gear. On later CT-90s and all CT-110s, you can also hook your toe under the front of the gear lever, like many other bikes, and pull yourself up into gear. Do whatever suits you.

The CT series has a lot of torque at low RPMs, so it will take off with quite a bit of power. The throttle, though, has a very weak return spring, unlike a lot of bigger bikes. Therefore, you get thrown back on the saddle, which pulls on your arms, which rotates your wrists, which tends to crank the throttle open, which tends to throw you off the back of the bike. A lot of CTs have small dents in them because somebody did this without realizing what might happen. Be careful, and do not “arch” your right wrist when you take off. If all else fails, there’s a red kill switch near your right thumb.

Shift up through the gears as you would with any bike, but remember that there’s no clutch lever. Back off the gas, then just shift. Then open up the gas again.

If you want to climb hills, stop the bike. Put it in neutral (kick the front of the gear lever until you get the neutral light) and reach down below and inside your left heel. You’ll feel a small lever that is normally flipped toward the rear of the bike, in the “high” (road) position. Flip it forward into the “low” (trail) position. It’s not synchro, so you cannot do this while the bike is moving and it may not go all the way into low range easily. While pushing on the lever, roll the bike forward or back a couple of feet and it should click into range.

In low range, the torque is incredible, but the top speed is now only about 25mph. Be careful not to redline the bike, and do not try to do crazy things with it that might trash parts that are used to road torque. One common problem is broken rear spokes, and occasionally stripped teeth if the sprockets are worn. More often, people fall off the bike in 1st gear because top speed in 1st is only about three or four miles per hour, and they were expecting more. Be careful.

This is just about the most thorough Honda Trail 90 Shop manual I have found online. It covers everything from regular maintenace to detailed wiring diagrams and part numbers.

Cool Online Parts Microfiche

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Download a full-res version of the manual (ct90k2manual.zip – 4.6mb)