View Full Version : 350lbs. on a 350X

02-29-2008, 07:48 PM
Hello there, first time on this site. Seems like you guys have lots of experience with engine mods. So, I ask this....

I have a 1986 Honda ATC350X that's in great shape. I have had it since I was a kid, back in 1990. We use to go to Glamis Ca. Which for those of you who don't know the terrain, it's all sand dunes. Anywho, I have never had any problems getting where I "wanted" to go. However, I have not rode the bike for about 10yrs and recently found out my Dad was going to sell it. So I stepped in and purchased the bike from him. After all, it was my bike! But like most fathers are, I didn't pay for it, so it never was really mine:rolleyes:

Well, the problem is that I have since married and have two kids, and have taken up another hobby for the family, rather than just Boating. I am now about 100lbs. heavier than I use to be, and times have definatley changed. My brothers have Banshees, and I would like to not only keep up with them, but show them there older brother can still out ride them.

So, POWER becomes the issue. I have read plenty of your guys's posts on the topic, and now have the bug to pump it up! According to Mr ATC, seems like you can bore out the motor to as large as a 500cc. I would love to do something like that. But for one, how does this affect the reliability of the bike. A stock 350X is a mean machine, and amongst one of the most reliable bikes I have ever known of.
Also, I understand that once I go this route, it will most likely need to run on high octane fuel, which is no problem. However I can not find much info on the carburetors. Bigger displacement, means more fuel, right?

Bottom line is, I live in Orange County California. Can anybody direct me to a good shop that I can either take them the motor or bike to have the work done. I kind of prefere to do it all my self. I am a ASE master tech, but I work on cars and Heavy trucks. I will not be able to do the machine work my self, but would prefere to send out the parts, and have the work done by a professional. Then I will assemble it myself. I am looking for someone to do the head as well. After all, what's the point in going larger with out proper flow, right?

Any thoughts would be great. This seems to be awsome place to swapp, info and war stories. I look forward to jumping in. Thanks!

02-29-2008, 07:54 PM
350xs are great trikes and fast enough to keep up to some modern quads, but you have to remember the sand takes away alot of power also. Im sure if it was bored to 500cc's it would haul ass and do alot of hills with ease, but it would be a ticking time bomb. I really dont think it could beat banshees in the dunes, since thats what thoes things are best at. If you really want a serious dune machine I would look at a 250r and a 310 motor. Im sure that would keep up/beat modified banshees.

02-29-2008, 08:01 PM
:welcome: always nice to see another triker on here. anyways, if you want to go high performance, expect to spend some money. see these sites.

EDIT: yea like super90 said, if you want to beat banshees, i suggest getting a 1985-1986 250R, Tri-z, or Tecate 3.

02-29-2008, 09:05 PM
3Wheelers4Life, Thank You!

The Goat
02-29-2008, 09:29 PM
also...google for L.A. sleeve...they offer some big bore kits and porting and such...not too far from you if memory serves.

03-01-2008, 01:12 AM
do a nice mild build with a big cam, big bore (nothing too big), head work and a 400 ex carb. like was said above you aint ever going to catch them up the hills or on sand high way, but they will burn 3x's the gas as you do. so all you have to do is ride a sweet, strong running trike and give them hell everytime they have to fuel up. :D

first time i was EVER in the sand was on my 350x in my sig, and let me tell you it was a life changing expericence. GREAT time GREAT ppl GREAT RIDING!!! but i was SCARED the first time out let me tell you...i still pull a piece of the seat cover out of my *Edited**Edited**Edited**Edited**Edited* every once and a while. LOL

03-01-2008, 05:57 AM
ha, ha, I know what you mean. I really am quite the opposite. Very little experience on other terrain. All I really know is the sand. I know it takes away a lot of power, but it is my game. Given a lot of thought, what I am most likely going to do is buy another motor, and have that one built. This way I keep my original as is. This bike has sentimental value to me, and I more than likely will not go so big. My concern is like I say in the title, I weigh 350lbs, and that is a major kill right there.

I have noticed the emphasis on beating Banshees. Yes I did say that, but I am more concerned with not Bogging out on a climb. After all, only 1 or 2 of the rides per trip would be a balls out run with the younger guys. I am turning into an old man, and I have a family. I really can't afford to go out there and kill myself. That's why I prefere the ATC. not too many people prefere the trike over a quad. But me, the front end just seems way too heavy. Maybe when I am much older, but now- it's ATC for me all the way..
besides, most of my riding is at the back of the group, keeping the kids in site. They tend to get lost in the dunes.

I really appreciate all the feed back. Feel like riding right now, But River season is around the corner. I need to get the boat ready. Thanks!

03-01-2008, 06:14 AM
my intent was to say that I prefere the ATC, because it is more challenging to ride. Quads are flat out boring.

03-01-2008, 01:20 PM
I don't know if that is possible with a 350x, but with a 250r... you should put them to the test.

03-01-2008, 02:20 PM
yea the 350 isnt too much for speed. you could juice it up but i dont think it will hang with a shee. you may (depending on condition) sell the 350 and get a 250R and juice that up. it has a better chance against a shee than a 350 does.

just my 2 cents

The Goat
03-01-2008, 09:16 PM
i'd say it would all depend on terrain really. you can throw down some serious torque with that "350" from what I'm seeing.

i'd say just put a new cam, rockers, springs, and possible big bore, and have some fun with it. talk to swigin, he's the resident guru.

03-01-2008, 10:22 PM
Heres a pretty good website with big bore kits, stroker cranks, and cams


09-19-2008, 08:48 PM
Hey all, Been away from the site for a while, just wanted to say thank you very much for your suggestions. Recently I bought my son a off road go kart, and want to modify that.
You guys are right though, I would be better off trying to accomplish the feat with a 250r. However I come to the reality that I am no longer a kid, and don't need to compete with the kids anymore. I am going to end up selling my boat to get a buggy, and just play with my kids.
Again, Thanks all

--- Three points are the most solid base a object can have---ATC's :w00t:

The Goat
09-19-2008, 11:56 PM
at about 3 myself, with the high comp piston, valve work, FCR, and clutch springs, it is impossible to stay on it and keep the front end down with 20s and 14/42 gearing.

200x Basket
09-20-2008, 12:13 AM
how about a diet? cheaper and better for you :)

just a thought :)

09-20-2008, 05:01 AM
Good Point!
Ha, Ha, been trying for years my friend, been trying for years. Guess I just love BBQ too damn much, had "the sugar" for years too, also smoke, everybody tells me I am killing myself, guess I am just too hard headed. Or weak, however you may see it.

Gets expensive too, need extra horsepower just to play.
oh well, I am sure it will catch up to me one day, Just always been the jolly fat cool guy everybody hung around, I never seen it as a problem, till I hit my 30's and my kids started chowing down. It's the last thing I want for them.

Thanks for the post! Got me thinking.

By the way, Goat, you have me thinking, I noticed you mentioned 14/42 gears, Can you tell me if that is stock? I am looking into parts and am going to start on this project soon. Noticed I can get as low as a 12 tooth front sprocket and 40 tooth rear sproket. Like I said, Not too concerned with top end speed, Mainly torque. In the sand I have never even seen 6th gear let alone 5th is very rare.

Any thoughts?

10-06-2008, 01:43 AM
guess I could put a stop to this thread. Took all of your guys's advice and got the 86' 250r


10-06-2008, 11:52 AM
Dude! Nice bike! A set of sand paddles and you will be rippin up them dunes!

10-06-2008, 02:01 PM
Nice score my friend! You'll give those banshees a run now for sure. Now if you could only keep up with the Tecates-:D

10-06-2008, 03:04 PM
Thanks, The guy threw in a set of paddles, but they are from 86 too.
rims are good
thats easy

fabiodriven-you have no idea how close I came to getting a tecate-lol