My Honda Trail 70 and Street Legal Conversion Tips

Here she is getting carried home in a Ford Escort after a fun
night riding Pismo Beach dunes on New Years Eve.
(Jan 2012 New Years day)

I bought a 1974 Honda Trail 70 in October 2011. Payed $600 for it. It had a '75 CT70 engine in it that somewhat ran. The original engine came with the bike but was disassembled and in a bucket. I didn't know it at the time, but this would be the best motorcycle purchase I would ever make.

What she looked like the day I got it street legal.
That horn mount is UGLY, but legal.

The Purchase:

When I bought the Trail 70 it was not it good condition. I paid $600 for the bike and a mostly disassembled spare engine in a bucket. The tires were cracked, suspension was blown and the stock folding handlebars had been replaced by BMX style bars that were always loose. It did however have a lot of good things going for it. The brakes and engine worked enough for a test ride and the overall condition of the paint, chrome and seat were good.

Cracked Tires

Paint and original stickers in good condition.

Sorting out the Paperwork: Bill of Sale Issues

My Trail 70 didn't come with much paperwork. I had a very basic hand written bill of sale, instead of a pink slip, which can be very risky. The bike could have been stolen or maybe it was registered and had hundreds of dollars of back fees. There are ways to check this but it's the buyers responsibility. You can call the local Department of Motor Vehicles and Highway Patrol office to ask these questions but they aren't always helpful. I would recommend calling anyway if you are in doubt. I didn't call back when I bought my Trail 70 and luckily it worked out ok. It wasn't stolen and there were no back fees owed.

Typical Bill of Sale:
Make two copies. One for the seller and one for the buyer.
I the purchaser, (Your Name), hereby purchase this (Make, Model & Year of bike) with vehicle identification number (VIN of Bike) in as is condition on the date of (Date) from the seller, (Name of Seller), for an amount of ($). (Sellers Signature) (Owners Signature) 
To sort out the paperwork I first took the bike to the DMV. After waiting in line for a while they said my Trail 70 wasn't in their records. I've always heard that if a vehicle isn't registered for 7 years then the DMV assumes it was destroyed and deletes their records. To get it back in the system a VIN verification needs to be performed. Usually this is done at a local Highway Patrol office. A VIN verification is where they read the VIN, Vehicle Identification Number, to see if its stolen and determine if the physical bike matches what the VIN decodes to. Such as make, model, year and engine type. If its not stolen then they give you a paper saying the year and model of your bike. For me the highway patrolman at the front desk did a google search for "Trail 70 VIN decoder" and used one of the websites to figure out the year and model number. Not the most accurate way but I can't complain. With this done I returned to the DMV and was able to get a pink slip and a green off-road registration sticker. Not bad for a days work but I had a long way to go for street legal status.

Update: On a recent Buell project I was able to do a VIN verification at the local AAA office. You have to be a AAA member but it was so worth the $50 annual member fee to not have to deal with the DMV.

Converting from Offroad Green Sticker to California Street Legal:

For street legal status I first had to make the bike physically street legal in California and pass a brake and lamp inspection. A brake and lamp inspection is where a local motorcycle shop looks over your bike and makes sure all of your safety equipment works. My Trail 70 needed everything; blinkers, a horn, a mirror, a brake lite for front and rear brakes and a headlight with high and low beams. A mirror was something I had in my junk pile. Brake lights were a bit tricky but being able to buy all the original switches and wiring harnesses from was a big help. The blinkers and horn I used were modern 12V ones from my Honda Hawk.... Wait a minute? How did that work with the 6V system on the Trail 70? It didn't, I ran a separate wiring harness from a small 12V battery. If you look carefully at the picture above you can see all the excess red wire spaghetti jumbled behind the headlamp bucket. It wasn't pretty but all of this tinkering was good enough to pass a Brake and Lamp Inspection.

Once I passed the Brake and Lamp Inspection I took it back to the DMV, paid a bunch of fees and walked out with a shiny new license plate. If I remember right all the fees and inspections totaled about $300. That's not including the parts. After I got the street legal status the blinkers and horn came back off. I then rode it this way for months until I had enough money for some upgrades.

Upgrades, Stories and Random Pictures:

The original rusted and badly painted exhaust was falling apart so I replaced it with a new Chinese replica from This was probably a bad idea because over the last 6 years the replica has broken and been welded back together twice. Unfortunately I gave the original exhaust away to a fellow Trail 70 enthusiast.

110cc semi-auto engine and newly added rack with ammo can. (Summer 2012)
When I bought my Trail 70 it came with a spare engine in a bucket. I have no idea which one of the two was the original engine shipped in my Trail 70 when new. Maybe neither were the original. I used the best parts of these two engines to make one reliable franken-engine. I ran the franken-engine for about a year before I gave up on it. The original engines are geared too low, don't produce much power and are wired to produce 6V. All of these problems can be changed but I decided to install a bigger aftermarket engine. Luckily I had a 3 speed semi-auto electric start 110cc Lifan engine sitting in my garage. This was a great engine and I used it for about a year until I had an idea. The pit bike I never ride has a 4 speed manual 125cc "Xtreme" engine in it. Why not do an engine swap, gain a 4th gear, a clutch and some extra power? This was a great choice and I wish I had stopped there because about a year later I upgraded one more time. I bought a new Piranha 140cc engine from (Link to the one I bought) If you are counting, the Piranha is now the 5th engine bolted into my Trail 70 since I've owned it.

Engine pile. Some stock Z50 and CT70 engines
with the Xtreme 125 on the right.

The 125cc "Xtreme" 4 speed manual engine from my pit bike.

The Piranha 140cc has been a great bolt in engine but I think the 125cc is a better choice. A 15cc difference isn't much but it definitely makes a difference. The Trail 70 has a very short wheel base so the extra torque of the Piranha 140cc engine makes taking off a little difficult if you want to keep both wheels on the ground. I got use to it after a while and grew accustomed to taking off with the engine just above idle. But, I really miss the fun of leaning forward, twisting to full throttle and taking off with a slight wheelie and max acceleration. It was really fun and easy because the 125cc engine seemed to have the perfect amount of power for the Trail 70.

The Piranha 140cc got me to Yosemite National Park.
Read about that trip here.

My Trail 70 decked out with American flags for the
2012 San Diego Pride Parade. (July 2012)

The front suspension had been destroyed for probably the last 20 years so I decided to rebuild it. (When I finally took it apart sand from Pismo Beach came out.) I bought oversized springs from as well as a rebuild kit for all the seals. This was by far the best choice. It still has the same stock looking front forks but is now better suited for a full sized rider. The rear suspension was also upgraded later but with stock looking oversized rear coils. I don't have good pictures showing a comparison.
Old springs on the left, new on the right. (Aug 2012)
With front suspension removed. (Aug 2012)

Broken speedometer cable.

Installing this ammo can was the best mod I ever did.


  1. Can you do all the street legal process and certification at AAA too ?
    I would like to avoid the DMV at all costs!
    I just finished fixing up my CT70 - all lights, horn, mirrors fixed and good as new! Im ready for the streets!

    Also, do you need some sort of separate motorcycle license in CA ?


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