LA-Barstow to Vegas on Vintage CT90s

[adventureduo]

So, about 9 months ago a few of us came up with this silly idea that we could ride the famous LA-Barstow to Vegas ride on 90cc bikes. Our thought was, anyone can do it a real bike... let's make it a challenge. It's only 450-500 miles off road in two days starting in Palmdale CA and ending in Las Vegas Nevada. What could go wrong?

If you've never heard of the LA-B to V... it's about as oldschool as it gets and used to be wide open across the desert.
More information here: http://www.labarstowvegas.com/

If you're not familiar with the Honda Trail90, it's basically a small trail bike that offered a low range drive kit that basically let the bike climb like a goat over very technical and steep terrain. Hunters used them and they were big in the RV world, hauling them on the back bumper and such. Also, most people remember learning how to ride a 2wheel moto on these when they were a kid. I don't know many people that don't point when you're out putting around on one.

Some of you know that Yoshi has her 1978 CT90, but as prestine as it is she'd absolutely kill me if i tore it through the desert and beat it to death. So the craigslist hunt was on for a cheap bike that i wouldn't feel bad about tearing up a bit. My thought was, get something somewhat cheap.. running or not, rebuild it, run it and then sell it afterwards.

For $300 I found this. A 1969 k1-b. No paperwork and no longer in the CA DMV system.

It was a non-runner and missing quite a bit of small misc parts, but it was a solid platform. Besides, the rebuild was the fun part!

The '69.5 was also the First half year of the Telescoping fork - a must have, since the suspension already is terrible for what we're doing. The springer type front would not cut it for what we were trying to accomplish. Additionally, the engine air intake was moved to be "out of the way", on the left side of the frame, below the seat. However, this lowered the height of the air intake, thus restricting the ability of the CT to cross deep streams.


The kid we picked it up from was working on it as a project bike to take him back and forth to school. He ended up giving up as he ran out of time before the school year supposedly started. To me, i think he may have gotten in over his head as we would later find out the top end was seized.

It was time to get it in the shop and get it running. First order of business was, i needed it to "roll". The front tube was flat and the tire seemed to be at least 20 years old. So i yanked that first and replaced both.


The front wheel received a new rim strap too. The old one was done.


Next on the list is to chase the sketchy wiring harness and see if i can even get the electrical to work, afterall, if i can't get that set straight it doesn't matter if the motor is mint. It's not running without ignition. After robbing peter to pay paul and using Yosh's battery to test, a bit of tracking down schematics and chasing 30+ year old wiring i got the wiring figured out. I was happy to see everything work how it should. I also, forgot to mention that the bike didn't come with any keys. So that would have to be ordered next.


I found this place online, hondakeys.com. They actually have NOS cut original keys in stock. Only certain model years, but i was lucky. All i needed to do was send them in the tumbler id number and within about a week i had a key that worked.


The battery was missing and so was the the holder and cover. So i figured i'd order up some parts from dratv.com, somehow i knew it wasn't going to be the last It was amazing to see just how many genuine Honda parts that are still available out there.


The battery hold down bracket arrived and it was a later model year. All you can get these days. So i had to grind and modify it to work.

 

[adventureduo]

After modifying the battery hold down bracket, it was time to fill the battery with acid. They don't ship these 6 volt batteries ready to go and it's not something you want to monkey around with. I was fortunate to get the assistance of Matt over at Insideline Moto to help fill it.


Fresh battery in and wired up properly.


New battery cover installed and secured.


Next step was drain the oil, and add new. Lord knows when that was done last. Probably wasn't the smartest idea to put amsoil in it right off the bat, but it was all i had on the shelf. Remember, we hadn't even tried to fire the old girl yet.


So here's where the smooth rebuild gets a huge speed bump thrown at it. We try and fire the old girl and she's not responding. Check compression, valves and spark, everything seems somewhat ok, until we realized when we pull the head that the piston is seized up! Not to worry, we knew that this wasn't a runner, we just didn't know how bad.

Time to rip her apart. Turns out, we think that someone must have ran a water hose down the exhaust. The inside wall was rusted and the piston was seized badly.


So when life gives you lemons, your make lemonade right? Time to order a big bore kit and get the head out to the machine shop. :ylsmoke:

Dr. Atv was starting to like me even more.. while i was ordering the big bore kit, we also replaced the valve springs and other such items while we were there. I also ordered the performance cam. I was excited to get the thing back together but i knew it would be at least a week or two for the machine shop to get the head done.


So while i was waiting for the machinist to call, i tackled other items that needed attention.

That old duct tape seat wouldn't do. It was time to install a new cover.


The rear sprocket rubber cushions were not even on the bike. So those went in next. Note how Honda was smart in their design where the sprocket is connected to the swingarm for ease of changing the wheel on the trail.

 

[adventureduo]

The rubber cushions going in. These are very critical components to the drivetrain.



While repairing and yanking the wheel, the chain snapped. If it breaks that easy, it's probably time for a new one after 40+ years!


Time to head back over to our boys at InsideLine Moto for a new chain. They don't just work on KTM's!


New chain going in and cutting a few links. There's one bike still sold today that uses this type that Honda sells, i want to say it's like a 70cc or something. Can't quite remember.


It was almost time to pickup the head from the machinist it was time for new fuel lines. The old ones were original to the bike and the carb barbs leaked.

 

[adventureduo]

New lines going in, the tank is the seat for those that don't know. A coat hanger is your friend for this part.






With more to do, the call from the machinists comes in and the engine gets first priority. We get to work.






Get it back together and see if she'll fire. Exciting times.

 

[adventureduo]

We get the bike fired, but notice the carb is leaking really badly. Before we re-assembled we took the carb apart and cleaned it in the electrolosys machine. Didn't help. Time to figure out a solution for that. Going to be tricky though as the '69 carbs are obsolete and were their own beast with a different bend than the rest. My solution is to order a simple 22mm intake manifold and a 22mm carb. Stock is 19mm.

A buddy fabs up the intake and mates it. From what i've read online, this is one of the only ways to mount a larger carb on a older CT. In hindsight, i wish i would of ported and polished the intake to 22mm, but it will be fine necking down. After all, it's a 104 cc now.


The CT104 will now breath through a K&N instead of finding the stock configuration which is nearly impossible to locate. The other guys in the race will be running UNI's. Problably a better idea, but i had this already. On race day it will get womens nylon leggings as dust filtration.

 

[TCcruzn]

I can't wait to see how you fix up the bike. I just came home with a '67 trail 90 with the same low range option. The bike runs so I will try it out next weekend.

 

[psykokid]

Those are fun bikes, my wife's uncle has one that he bought new, still has and takes it out and rides it in the dirt quite often. Gotta love the trail gear.. One of the main reasons parts are still available is that you can still buy the same basic bike (although with a roaring 105CC motor in the CT110) in other places such as Australia where they are known as "Posties" because the mailmen ride them to do deliveries.

 

[1leglance]

Holy Crap that is way cool.....been seeing hints of this on Facebook but great to see the build here.

Now I gotta be the bad guy and ask if your "cheap" project didn't blow out a big budget? Looking back would you say it would have been better to spend more up front on a decent runner?
Only asking because I am thinking of something like this for my 14yr old son as a trail bike to take on trips and need to know cost of rebuild vs buying nicer up front.
thanks

 

[adventureduo]

Time for a front fork seal rebuild. The forks were leaking and the shock boots were missing. No bueno.

The forks had 43 years worth of grim on them in the triple tree area. Needless to say they took a bit of persuading!

After about a good 45 minutes, i finally got one side loose.

 

[adventureduo]

Time for new fork seals. Finding the C-clip in the fork can be fun, since it's covered in years of grime.



Separating the forks from the leg is quite interesting as well, since you need to yank like a madman to get them to come apart.



All buttoned back up, new fork boots on too. All Honda OEM.

 

[adventureduo]

New fork springs go in after taking weeks to clear customs. They prove to be worth the wait in the end.




Refill the forks with nothing but the best right?

 

[adventureduo]

Lance,

You hit the nail on the head. For the money im into this bike, i could of bought one in decent running shape and ready to go. But, im the kind of guy that likes to know how to work on things in the middle of no where. I feel more prepared and more rewarded knowing that we did the work before, ourselves vs.. guessing what could go wrong.

The other thing is, after the race... making it the whole way god willing, the bike will mean more to me then than ever before and i already think it's going to be tough for me to let it go.

Holy Crap that is way cool.....been seeing hints of this on Facebook but great to see the build here.

Now I gotta be the bad guy and ask if your "cheap" project didn't blow out a big budget? Looking back would you say it would have been better to spend more up front on a decent runner?
Only asking because I am thinking of something like this for my 14yr old son as a trail bike to take on trips and need to know cost of rebuild vs buying nicer up front.
thanks

 

[adventureduo]

Roll Chart Installed for turn by turn directions. The LA-Barstow to Vegas coordinators will not accept anyone particpating, NOT to have one. They like the old trusty ways of life. You're allowed to carry a GPS and will get coords morning of, but every bike has to have a roll chart. The funny part is, we don't have re-settable odometers Thankfully, we'll have a GPS unit with us, and we can reset and zero out that way too.

 

[adventureduo]

The front fender was mangled a little and there was a big crack in it. Welded back up and working perfect again. Also, you'll notice plenty of room for the nobby tire.


I found that my rear tool bag from the dual sport had the same arch as the front fender of the CT90. So i used it to carry spare tools/tubes.


Next i wanted to be able to carry more fuel. If you look at the smaller Rotopax, they're generally pretty perfect for many applications. The 1.75gal rotopax fits the rear rack absolutely perfect. So it was time to mount. This also doubled the range of the bike, since the stock tank is 1.75gal.

 

[teotwaki]

Lance,

You hit the nail on the head. For the money im into this bike, i could of bought one in decent running shape and ready to go. But, im the kind of guy that likes to know how to work on things in the middle of no where. I feel more prepared and more rewarded knowing that we did the work before, ourselves vs.. guessing what could go wrong.

The other thing is, after the race... making it the whole way god willing, the bike will mean more to me then than ever before and i already think it's going to be tough for me to let it go.

TRUE times 2!!

You rock Dave.