2nd Aug 2009, 12:59

I recently bought a 1970 Honda Trail 90 off ebay. I still have not got it running, it has lots of compression, but it just won't spark. I looked at the points and they seemed to be OK. What could the problem be? Email chrsbsh1@gmail.com. Thanks!!

21st Aug 2009, 22:48

Hi, thanks for your time as you read this, but I own a 1973 Honda Trail CT90 and it ran fine and dandy, but a little rough, so I thought I would tune it up a bit and cleaned the plug, therefore changing the oil...

After I changed the oil, I continued to start, and it ran for a minute and all of a sudden it just ran out of power; it was kinda weird, like the head light slowly faded away and now it won't start. Any suggestions would be appreciated. Again thanks for your time...???

9th Sep 2009, 21:35

Hey, I'm considering buying a 1970 CT-90. There is one for sale down the road. It is clean as can be on the outside, and it has about 3000 miles. What are some things to ask or check for when I go and talk to this guy/test drive? Thanks!

10th Oct 2009, 14:40

I just got a 1968 CT 90, and it has the 2 sprockets on the rear wheel, how did this work? Is it the chain length that changes?


24th Oct 2009, 15:37

The '68 ct-90's had an additional length of chain that had to be manually installed to use low range.

Disconnect the master link, add an additional chain, place the chain on a larger sprocket.

Viola, low range.

22nd Apr 2010, 10:22

Hey, the other day I started to restore my Honda CT, and I don't want any wires, I just want the main wires to get it running. Does anyone know where I hook the wires into to get it running? Let me know. There are also wires coming out from the motor; what are they? Thanks.

3rd Jun 2011, 14:12

Hook the green ground wire to a good ground on the bikes frame, and twist the two positive battery wires together. You should get spark, and it will run fine without a battery.

7th Jun 2011, 17:42

I also own a 1971 CT; would not part with it.

30th Jun 2011, 19:13

I connected the two battery wires together, and ground the green earth wire; still no spark. Where do I look next?

Regards, Mick.

26th Jul 2011, 23:20

Which rectifier did you use from radio shack?

Thanks Randy Driver copycat513@netzero.net

31st Jul 2011, 02:36

What is the best off-road engine you can put into a Honda CT90? -holden


29th Oct 2011, 18:55

Just bought a 71 Trail 90. No title. I live in Ohio, can I get a title for it or not? Gave 450 for it, and it is near perfect physical shape with 2000k on her, but can't get a spark as it has sat for over 2 years. Any thoughts on this would be appreciated.

Also, had one in my youth. It was worn out when I got it, and I couldn't kill it, so I got married and gave it to my brother in law; he killed it.

Thanks in advance.

21st Dec 2011, 22:12

To use the big sprocket, you need to add chain links. I had a 1964 Trail 90 in 1965 when I lived in Alaska, and it was the best bike for going in the woods fishing. I only used the big sprocket one time, and never had to use it again. I left Alaska in 1969, and now live in Fort Lauderdale and am looking for another to explore the Everglades and more fishing.


26th Jan 2012, 14:08

Yeah, go to Radio Shack and pick up a rectifier, and do the Radio Shack rectifier upgrade. Everyone does it, and it's ONE OF THE BEST upgrades for dirt cheap you can do.

You need the following:

18 gauge wire (4 pieces of 2in 18 gauge wire).

4 butt connectors.

4 female spade connectors.

Some shrink wrap if you feel inclined to do so, and the actual rectifier --- 3.55 plus tax. LOL cheap, but WAY BETTER than OEM.

Then hook up the wires accordingly.

12th Apr 2012, 11:37

The battery is the voltage regulator. A new battery seems to eliminate all the electrical problems. They were made before it was mandatory for bikes to have their lights always on, so I think that they use more juice from the battery when idling, than the engine is able to recharge the battery. If you do a lot of idling with the lights on, it may drain the battery faster than it is recharged. I got in the habit of turning off the lights when stopped, and back on when going, except at night, but new batteries work best in all situations.

23rd Apr 2012, 00:50

Your problem sounds like a carburetor issue. Rebuild kits are cheap, and I'm sure there is a YouTube video to show you how. Good luck.

13th May 2012, 05:27

My boy bought a Chinese LEI Motocross jump bike, took the 125cc motor out and put it into his Trail 90 Honda. This left the Chinese jump bike without a motor and he was going to scrap it. Adapting the jump bike's lugs with my home made adapter fittings to the Honda motor, I succeeded to fit the motor and to line up the sprockets. Now I have a problem with the electrics, and a wiring diagram would be helpful. No lights, so no battery on these bikes. A cheap electronic ignition with low voltage to the points system could be the trick.

Can anybody help? E mail me - stardust_27@optusnet.com.au

Ziggy Ozzie Australia.

1st Aug 2012, 15:24

Get one from Radio Shack.

10th Sep 2012, 13:50

You need to have a good, fully charged battery. Even though this bike is a kick start, the battery needs to be strong enough to run the headlight AND supply spark. Charge it and you'll see. Then go get a new battery and it will run. I just went through the same thing. Mine is a 68 and it's 6 volt. I put mine on a battery tender about once a week, because these bikes are known for a weak charging system, especially if you use it as little as I do.

3rd Nov 2012, 11:46

Will not shut off with the switch. Can it be the rectifier?

30th Aug 2013, 09:04

In the left side cover of the bike, they came with a section of chain and tools to disconnect the master link of the chain and add the additional piece. It makes the gearing so low that you could probably tow a travel trailer with it (LOL).

8th Apr 2016, 01:43

Get the key number off the lock. You can purchase one off of eBay. I did it; the key works great. It's same key for all the locks on the bike.

8th Apr 2016, 01:50

The seal costs under ten bucks at Honda. Yes they are still available. But do yourself a favor - change both seals while you have it apart; one at the back of the high-low transmission shifter, and the other one behind the sprocket.