About to start the next project 1977 ATC 90 any suggestions?

[Zach]

History - I decided to get it out of the grass and pull it into the shop. In highschool I stripped this thing down to the frame painted the frame, got a nice set of fiberglass fenders for free from one of my best friends who had them laying around (I love having friends I can trade parts and stuff with). When I disassembled the engine I found it had a very very large bore. This was about 10 years ago so I am going all by memory. I believe it has a Wiseco piston in it. I had contacted them and the guy literally laughed at me and said that kit hasnt been made sine the 80s. I was very discouraged and had no extra money because I only made $4.90 an hour back then and my pride and joy was my 65 Mustang. So it was put in the shop until I needed the room for another project and it got moved outside.

Present day- Its back in the shop, I had a couple people PM me about some parts. I went to get my handy snap on digital caliper to make some measurements and it has a dead battery. More information to come when I get it. I am very interested to se what this thing was bored out to. I am also very excited to get this 90 going. I grew up on that thing and as I remember it never had a pull start and always smoked like a pig. But it never stopped running.....

[Side Wayz]

Nice keep us posted I'm curious :wondering about the bore.:TrikesOwn

[harryredtrike]

put a few bucks in her,and get her going.i love the 90.

[hdeuce]

I just bought a 1978 -90cc a few weeks back. Well half of one. Orginal owner. Was ridden twice for about 10 minutes. Son drove into a tree and bent the forks. Parked outside since. I tore the whole bike down. Bought a new 22mm carb, 110cc intake, FMF KLX 110 exhaust, performance cam, new fenders front and back, new forks, tires, wheels yada yada yada. Rode it for the first time on Staurday. This thing rips. Fun bike. I'll post a pic shorlty.

[jb2wheels]

Looks like fun.

I have a 77 or 78 (need to check the frame again) with an 84 CDI 110 engine in it. It has fiberglass fenders, too. I'm still trying to figure out how to mount the seat. I have a good foam and cover, but I think I'm missing some pieces.

Good luck!

[Zach]

I am amazed at all the modifications you can do to these 90s it seems almost endless.

[shortline10]

I believe their were more aftermarket parts / options made for the atc 90/110 than any other ATC made . Just about every piece can be found aftermarket .

[hdeuce]

Here is the completed pic of mine.

List of upgrades:

Performance cam
22mm carb
FMF exhasut (KLX 110)

This thing rips. Very responsive. Hey shortline10 can you suggest any other upgrades? I was thinking of buying a big bore kit (piston and Jug) - is it that easy?

[Zach]

hey hdeuce what kind of front tire is that or is it a completely different front end too? I like it.

[hdeuce]

stock front end with a 200x wheel and 22" tire. Makes it look more racey..

[shortline10]

Here is the completed pic of mine.

List of upgrades:

Performance cam
22mm carb
FMF exhasut (KLX 110)

This thing rips. Very responsive. Hey shortline10 can you suggest any other upgrades? I was thinking of buying a big bore kit (piston and Jug) - is it that easy?

A big bore kit will give it a little more power and its not to hard if you know what your doing ;) .

[hdeuce]

so it's just the piston and jug? Seams pretty easy to install. Can you point me in the direction to buy one?

[shortline10]

so it's just the piston and jug? Seams pretty easy to install. Can you point me in the direction to buy one?

All you need is the piston kit and a decent gasket set . You can use your cylinder just need to get it bored at your local shop . do you have a 90 or 110 ?

[hdeuce]

1978 90cc. Bored at my local shop? Like a motorcycle shop?

[shortline10]

1978 90cc. Bored at my local shop? Like a motorcycle shop?

Yep , like your local motorcycle shop , if they dont bore cylinders they should know were to have it done . I have a few NOS big bore kits when your ready .

[hdeuce]

I'm ready, what do you have? Can you hook me up with a big bore piston and cylinder so I can just bolt it on?

[rdlsz24]

hdeuce your 90 reminds me of the GPX 177 that Edog built awhile back
http://www.3wheelerworldforums.com/showthread.php?t=91844

Rob

[hdeuce]

thats because I bought edogs bike and parted it out. There are quite a few remaining edog bike parts on this bike.

[Vealmonkey]

First all, get some new tires for that beastie and don't overinflate them. Treat your tires nicely, that is your only suspension for now. The biggest thing I find on the 90/110 engines is make sure the engines are properly tuned and running right. #2 make sure all your wheel bearing front and rear aren't causing any unnecessary drag on your engine, your are maybe talking 8hp here. Make sure your chain is properly adjusted and not hanging up and to make sure your rear brakes are set and working properly, once again to not cause any undue drag on the small engine. A nice free flowing air filter and a DG pipe will help wake the trike up and you may want to check your plug to make sure you don't have to rejet. Watch your riding with a free flowing air filter, I mean don't drive through lakes or really deep puddles and don't spray your garden hose directly at the air filter, you don't want your engine to eat alot of water or mud. A cam is a better initial investment than to just bore you cylinder out to the biggest bore, which can be wasteful if you are on a limited budget. Make sure your electrical connectors and ground are nice and corrosion free and making proper contact. It doesn't take much resistance in a 90/110 points system to really make the trike run rough. They are great trikes to learn maintenance and wrenching on. Parts are pretty cheap, I mean they had a 10 year jump start on other honda trikes except for the atc70, so they solid millions and there were tons of aftermarket parts. People just seem to like the bigger engined trikes so most 90/110 trikes get passed up on. You ain't seen nothing to you've seen the unlimited 90s powersliding sideways around a turn. I hope this gives you some ideas to think about. Have fun.

[hdeuce]

Took these today at lunch time. They look a little better,

[Dirtcrasher]

Looks pretty goid!!

[rdlsz24]

Oh I didn't realize. The 177 was the one that ran into a tree? You sold the GPX motor? I'm confused here.

Rob

[hdeuce]

No, the GPX 177 sat in my shed for to long and had to be parted out. This 1978 90cc was the one that ran into the tree and sat for many years until I got my hands on it. The result is another fun toy at my lake house. No clutch on the 90 (unlike the GPX) making it easier to ride around on :)