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dom
11-05-2008, 12:09 AM
Talk with these guys a few times and their prices seem pretty decent.

They sell the big bore kits for the 350x, which ups it to a 425cc, or a 452cc.

If I ever get a second engine for trike I will go with these guys.

Kustom Kraft (http://kustom-kraft.com/hondakits.html)

Canadian350X
11-19-2008, 01:24 AM
Wow, 425 & 452 cc kits. I imagine a 450 trike would be quite the weapon. I may have to investigate this option for my project.

Canadian350X
11-25-2008, 09:13 PM
I've also found these guys.

Powroll (http://www.powroll.com/P_HONDA_ATC350X.htm)

dom
11-25-2008, 10:52 PM
I would really like to find an extra motor to mess with. The one I have now is in perfect shape and I can't see cracking it open for no reason. I see motors on ebay all the time, but they go for waaay to much money. Finding a whole trike for sell that needs work would great.

Canadian350X
11-27-2008, 11:27 PM
Kinda like the one I got???:D:D:D

I've decided a budget of $1500 max to get this bike restored. If I can fit a BB kit into the mix without breaking the bank then I'll do it, otherwise I'll stick with a stock refresh.

Lucky for me I used to work at a snowmobile/small engine shop and still have a good relationship with the owner so I get all of my parts at or a little above cost.;)

I wish I had a heated garage to start working on this thing......

mattpiston
01-21-2009, 06:32 PM
yeah i know this is kind of an old thread but did anyone ever put the 425 bb kit on? how much power did it increase? would i be better off going with a stroker kit from powroll 37fcr carb,performance exhaust and stage 2 cam i hear that just stroking it will give you more power than the bb will. is this true?

dom
01-21-2009, 09:51 PM
Stroking will give you more power for sure! Just think of it like this, when you make a stroker motor you are increasing the leverage and torque of the motor (hence stroker). We don't have anybody here I know of that bolted on a bb kit.

"More displacement and greater leverage means more torque."

What does that stroker kit you are talking about increase your displacement to, cubic centimeters? Actually I just looked, does 393cc sound right?

If you have the money and the balls to ride the thing when you are finished building it, I say go for the stoker kit!

Hope my $0.02 helps..

Oh, and welcome to the site!

mattpiston
01-21-2009, 10:53 PM
yeah your .02 helped. well i have 3 350x and one is all stock the other one is bored .040 over camed and bigger carb and i built a header and exhaust for it. they bolth run good really reliable i built the one that slightly worked over when i was 10 and just recently gave it to my brother so now i need to build a strong running engine in my third one....my third one is one im currently building. i bought it for 400 dollars and some guy ruined it by putting a quad front end on it:mad:.....it hasnt ran in 6 years but i cleaned the carb and had it runing in a few hours so now i bought a rolling 350x frame and am putting it together. i just split the crank case today and am fixing to send in my crank to get stroked im hoping it will be the power im looking for if not i may haft to put a bb on top of that lol. do you know if dueling the exhaust hurts the power any? i have dueled exhaust on my brother...had...he wrecked it at the dunes last weekend buckkled the forks and tripple trees...good thing i have alot of spares lol. she is going again though! Thanks guys....well i figured since i have a 350x i might as well be on the site and maybe i can help with some problems or issues. and actually i think its a 381.3cc if my math is correct.

dom
01-21-2009, 11:14 PM
Check out this page POWROLL (http://www.powroll.com/P_HONDA_ATC350X.htm). It looks like it has everything you are looking for. It looks like you can get up to 430cc just off the stroke. Then I guess you could go extra big cc if you get the big bore kit too. I am wonder if it works like this..

Stock 350cc increases to 430cc with the stroke, so 80cc increase.
Big Bore kit is 393cc, wonder if that stroked crank would increase that too 473cc?

I think it is worth shooting them people an email and asking.

BB kit + machine work to stroke + race cam = $810

Plus you would wanna get some quality internals too, springs/gaskets etc..
Then a big azz carb too. We are talking about $1,000.

Dude, just thinking about that much power on a three wheeler scares me!

Sounds awesome though. I wonder if it would be able to defeat those fast 450cc quads out there?

As far at the dual exhaust, I have no clue. I imagine trial and error, or better yet finding a place that could dyno your engine for you.

mattpiston
01-22-2009, 06:39 PM
yeah i know where a dyno is...there is one at the sand dunes that isnt far from my house. i plan on putting it on there and seeing what she will do when i get my motor back together :).....im hoping on some power lol. i think they will jet my carb for me to...i will jet it and see how close i get just using my head...im gonna jet rich untill she get broke in then take to dyno.

dom
01-22-2009, 10:01 PM
Are you going to do the big bore kit, stroker, and cam? I bet if you do that and have a carb up to the task you will be cranking out better than 40 horsepower. I have been on the lookout for an extra engine to tinker with and do something like that myself.

mattpiston
01-22-2009, 10:54 PM
yeah im going to upgrade my valves do some port work send in my crank to stroke and put on the bigbore kit and 37mm fcr. im not sure how much it will put out i was guessing high 30's low 40's...but we will know forsure when it hits the dyno. thats if i put the engine back together the right way hehe! this engine here is my backup enging i bought last weekend so i figured i would just build it up :)....i will post some pic's of my engine assembly and then of the finished project. it may not be pretty i dont have good plastics for this one yet...i figured i would just make power and looks later lol.

dom
01-23-2009, 01:00 AM
Yeah, build it first then make it shine. So you are going to drop over 1k on the engine?

Where did you pick up the extra engine?

mattpiston
01-23-2009, 03:58 PM
i picked up the engine in tulsa....a guy had it setting outside mounted on an atv frame it was setting outside for 6 years nothing covering it so i got it cheap. brought it home at 2 in the morning had it runing and driving by 5 in the morning and my buddy rode it all day at the dunes at 10 am. its a good engine no smoke lots of compression.and yeah probably around 1k lol. i got to look in my storage shed i think i have a carborator for it but it maybe to big...we will just haft to wait and see how it does with it...if it works i will save some money there.

mattpiston
01-23-2009, 11:35 PM
has anyone used the 425bb kit in the 350x? how much power gain is it? whats the reliablility on this?

dom
02-11-2009, 12:09 AM
If you are just going with a big bore kit, no stroking and no cam there should not be any difference in reliability at all. Is that kit just a larger jug, or does it involve stroking too?

superchomper2003
10-28-2009, 10:40 AM
I know this is old but I wanna know the outcome! Im looking for a way to make my trike beat my buddys 450s.

dom
10-28-2009, 11:38 AM
Dude, I'm not even sure that is possible!

Those 450s rev up like two strokes.

GeoD
10-28-2009, 01:57 PM
Check the Master Parts List.

There are several Big Bore Kit places listed. There's one that makes a 452cc kit. Im going to recommend a dual oil cooler if you go big bore.

Im guessing the 425cc kit will be able to beat the 450Rs since you won't have the extra tire and frame weight. Plus you won't have the radiator and coolant weight. Unfortunately, you might have a hard time keeping the front end down.

If you're really serious about a big bore kit and what it can do I would suggest contacting Mickey Dunlap from Four Stroke Tech or Bill from TPC Trikes and run the specs by them and see what they say and/or recommend. These guys have been racing and modifying trikes forever. Mickey was one of the OG's in wheeler racing.

Now, if you really want to beat the 450Rs you can always save up and buy a TPC Trike!! Its a 450R trike conversion. One of the baddest rides around!! Not to mention one of the nicest conversions ever designed.

http://www.tpctrikes.com

dom
10-28-2009, 02:07 PM
I am going to disagree man. I think the only way to beat one of these water cooled 450s is to have a water cooled 450. Even with the weight difference I think the 450 will eat a Honda 425x's lunch. An air cooled 425 is no competition for water cooled 450.

I do agree with you on the TPC trike though!

superchomper2003
10-28-2009, 03:18 PM
Yeah the tpc trike is awsome! But not gonna be going that rout. I figure if I can get 40+ hp out of the trike I could beat a slightly modded 450 because of the weight diff, I mean like the 450'x have arround 40hp stock little more little less depending on which one. But getting that kinda power outa the X motor may not be possible, I dunno thats why i wann see one finished up on the dyno!

dom
10-28-2009, 03:30 PM
First off, this is a very primative and basic equation I just had and subject to debate because there can be many variables (carb, exhaust, cam) and the synergistic effects thereof.

But here goes:


Stock = 26.4 hp
cc = 350.4

350.4/26.4 = 13.27

So, 1 horsepower per 13.27cc.

If, by adding 75 more cc using this basic math yields 75/13.27 = 5 more horsepower.

Totaling ~31.4 horsepower.

Mind you, carbing, caming, exhausting, and fine tuning may get you well over that 40hp.

But, remember horsepower does not mean a whole lot. It's the torque doing the work.

Shet, it might be possible!

GeoD
10-28-2009, 04:38 PM
I would have to see them lined up. But, Im putting my money on the modified X.

1. Even if you run out of motor by the end of the track you probably got the holeshot because of the enormous amount of torque the X will be producing. Remember, it will be bored out and crank work done. Also there's a possible cam, valves, springs, port job, jetted, piped, and upgraded air filter.

2. I have to put my money on the X. It's a three wheeler!! :D I gotta root for the underdog. Always have....always will! ;)

The X will have a disadvantage of trying to keep the front tire on the ground. It will also have to deal with increased engine heat. If those are dealt with I think you will have one ripper of a bike!! Not suggested for trail use!! :D

Last resort....you can always reach for the NOS!!

dom
10-28-2009, 07:59 PM
I think with a 12:1 piston, two huge oil coolers, a sweet cam, the big bore kit (425cc), case boring (if necessary), free flowing exhaust, big carb, and a sweet exhaust it's possible.

Wonder how much it would cost to do it all?

I will get a lottery ticket tomorrow!

note: I've heard rumors of a big bore kit in the 500cc range.

dom
10-28-2009, 09:00 PM
Dammit.

Well ya'll have me thinking now.

Race Cam $185
Rockers Reworked $65 x 4 Are there four rockers?
Stroked Crank $290
393 Big Bore Kit $335

Total: ~$1000
Plus: other odds and ends ~$500

So: Around $1500 we're talking business.

Aight, I'm getting a lottery ticket tomorrow for sure.

Plus I would need a engine to do this with, can't molest the one I have now. It runs perfect.

superchomper2003
10-28-2009, 10:41 PM
Yeah, I would want to buy another engine also because mine runs like a top! I already have another oil cooler so if I did the extra oil cooler mod i don't think I would have a prob with overheating at all. I don't trail ride anyway so thats not a concern. Would be so sweet to see there faces and see what they say when they get beat by a trike! There already amazed because I keep up with them around the track.

dom
10-29-2009, 12:11 AM
On top of beating them, you would be riding an antique!

superchomper2003
10-29-2009, 02:23 PM
Yeah, thats the best part!

GeoD
10-29-2009, 07:29 PM
Kustom-Kraft:

ATC 350X 1985 - 1986 452 Big Bore Kit
Includes sleeving or plating as needed,
piston kit, rings,pin,and gaskets.
* requires case boring/not inc. $479.00*

dom
10-29-2009, 07:31 PM
Nice deal.. That would be the ticket, then to stroke it too!

GeoD
10-29-2009, 07:49 PM
Four Stroke Tech will hook you up with a complete build!!!

http://www.fourstroketech.net/atc350xproducts.htm

They even include the secondary oil cooler!!

superchomper2003
10-29-2009, 08:12 PM
sweetness!

GeoD
10-29-2009, 08:32 PM
Now here would be one of the sickest rides around...


Four Stroke Tech TRX450R 530cc Big Bore!!! You know where Im going with this yet!?


TPC530R Three Wheeler!!! :D

http://www.fourstroketech.net/trx450rproducts.htm

dom
10-31-2009, 12:39 AM
I wish they would post estimated specs on torque and horsepower.

Personally, I think a worked (head, exhaust, cam, etc..) 450cc water cooled engine is more than enough for the weight of an atc.

Dammit, I have thousands tied up in a freaking hot rod & harley I never drive and nil on the unit I ride the most for fun..

I'm an idiot!

GeoD
10-31-2009, 10:50 PM
Naaaa. You're not an idiot dudeman. You just didn't get around to working the X over yet! You just got too many toyz!! LOL!!

Some sites have a dyno print out of different configurations. Maybe you can email the companies on the Master Parts List. If they send you some specs you can post them!!

dom
10-31-2009, 11:20 PM
That's a good idea. What I would really like to do is get the whole case, cylinder, and head done all at once and for one set price and be done with it.

Honestly, I am kind of hesitant to get started on it because I know I'm not going to half azz it and really drop some money on it. Wife is going to kill me.

This ain't going to happen for some time, still in the thinking process.

What do you think would be a good swing arm? Keep the stock deal, extend a little bit, get a beefer one?

I wanna hear what Bill from TPC has to say/post about the X frame he is tweaking now.

Unregistered
07-26-2010, 10:54 PM
I would really like to find an extra motor to mess with. The one I have now is in perfect shape and I can't see cracking it open for no reason. I see motors on ebay all the time, but they go for waaay to much money. Finding a whole trike for sell that needs work would great.

i have two extra motors and many extra parts i just picked up my dream wheeler 350x. two extra frames two extra motors three clutches exhaust ect.. just about everything you can emailme daniel_james_07@hotmail.com

Cuztom Racing
09-16-2010, 11:06 PM
Out of all these pages ive heard hardly anything about portwork! Head porting is EVERYTHING! I dont care how big a motor you have if the air flow isnt there the motor wont be shat! Im in the process of building a 400+cc 350x and it WILL atvery least make 50hp and stomp 'bolt on" 450's! My head head porter and i are working on a HV (high velosity) head thats going to flow awsome numbers!

Also I have a good buddy with a TC built 500cc (350x) and its a BEAST! Out runs most anything that pulls up beside it! So saying a 350x wont outrun a 450 is nonsence!

kt60016
09-16-2010, 11:10 PM
Out of all these pages ive heard hardly anything about portwork! Head porting is EVERYTHING! I dont care how big a motor you have if the air flow isnt there the motor wont be shat! Im in the process of building a 400+cc 350x and it WILL atvery least make 50hp and stomp 'bolt on" 450's! My head head porter and i are working on a HV (high velosity) head thats going to flow awsome numbers!

Also I have a good buddy with a TC built 500cc (350x) and its a BEAST! Out runs most anything that pulls up beside it! So saying a 350x wont outrun a 450 is nonsence!

keep us posted about this i am interested

Cuztom Racing
09-17-2010, 11:53 AM
Will do. Im calling and trying to find parts now.

MOB Racing
10-03-2010, 07:07 PM
452's can be fun. Good porting, a stock cam (still the best fun for anything other sand drangs) and some decent valve springs...........................
or just make it bigger..........we did!
Say 492cc's, 535 with a Powroll stroker.
There is no substitute for cubic inches........except cubic dollars!

Cuztom Racing
10-03-2010, 11:48 PM
452's can be fun. Good porting, a stock cam (still the best fun for anything other sand drangs) and some decent valve springs...........................
or just make it bigger..........we did!
Say 492cc's, 535 with a Powroll stroker.
There is no substitute for cubic inches........except cubic dollars!

Well, Mike with some help from yal it looks like i'll be running a 492! I sure would like to see yal run CP pstons tho. Cp already makes big bore pistons for the 350x just not quite that big but for a order or 4 pistons they will make you anything you want. I'll buy 2 of the pistons if you buy or find someone to buy the other two?! Let me know what you think. Oh and i replied to ya email, send u a few bikes of my bikes.

492cc of methonal guzzlin, fire blowing, skraight nastyness and coming to a track near you!

garycs
10-04-2010, 11:32 AM
I have a good friend that has a XL 350 Motor that has a 440 big bore kit.It just needs to be assembled.He told me he would sell it cheap.I just dont know if it will fit in a 350x frame.

MOB Racing
10-04-2010, 01:45 PM
Our pistons are done by JE Pistons. They went the extra mile when we could not get LA Sleeve to commit to making more kits unless we wanted 4 at full retail. Along with help from our friends at Dynoman Performance in Austin, our design was for a big bore that just makes the 350X do all the great things it does, just easier. We're both over 50 and for some reason, we enjoy riding slower...........most of the time. Also, we wanted to have a kit that would appeal to the TRX 350 & 350D folks. Four of the pistons have been spoken for, I'm finishing up a piston/cylinder set tonight that I have a set of cases ready for. ( I you have a 452 already, you will still need to open up the cases a bit more as our sleeve was designed so we could use up to a 98mm piston )
Keep tuned in, Glamis and Christmas are around the corner.
I'm NOT a dirt rider, I ride the "Grandpa" ATC 300SX with Pro-Link we built. 200X front end and ProLink make for a ride that keeps these old bones happy. If I need a thrill, I hop on my '82 stripped 'Wing and go play with the cars on the street.
When Mike (yes, we are both named Mike.....Mikes On Bikes....get it?) wants to get his jollies, we either fire up his ATC 500R or in an extreme "need for speed", break out the Hurricane sand dragster, fill the Nitrous bottle and point him in a straight line.

Cuztom Racing
10-04-2010, 05:05 PM
Our pistons are done by JE Pistons. They went the extra mile when we could not get LA Sleeve to commit to making more kits unless we wanted 4 at full retail. Along with help from our friends at Dynoman Performance in Austin, our design was for a big bore that just makes the 350X do all the great things it does, just easier. We're both over 50 and for some reason, we enjoy riding slower...........most of the time. Also, we wanted to have a kit that would appeal to the TRX 350 & 350D folks. Four of the pistons have been spoken for, I'm finishing up a piston/cylinder set tonight that I have a set of cases ready for. ( I you have a 452 already, you will still need to open up the cases a bit more as our sleeve was designed so we could use up to a 98mm piston )
Keep tuned in, Glamis and Christmas are around the corner.
I'm NOT a dirt rider, I ride the "Grandpa" ATC 300SX with Pro-Link we built. 200X front end and ProLink make for a ride that keeps these old bones happy. If I need a thrill, I hop on my '82 stripped 'Wing and go play with the cars on the street.
When Mike (yes, we are both named Mike.....Mikes On Bikes....get it?) wants to get his jollies, we either fire up his ATC 500R or in an extreme "need for speed", break out the Hurricane sand dragster, fill the Nitrous bottle and point him in a straight line.

Im 29yrs old but the excate same as you guys "MOST" of the time i like to ease around, look good on my cuztom builds and drink beer, and thats the full intentions of my 350x build. Its only when someone wants a shot at the title, that i break out the big guns, nitrous sniffing, methonal drinking raptors. I just threw that option out for the pistons cuz Cp is by far the best pistons on the market. I got the hook up with Cp and I may just have them build me a cuztom order of 4 pistons and just sale the other 2, i know people will jump all over em.

MOB Racing
10-04-2010, 06:04 PM
From ghoulies and ghosties, things that go bump in the night................
Alcohol swilling, nitrous wiffing Raptors.................
Gadzooks fair dinkum............the boy's insane! Sounds good to us!

3Wheeler
02-09-2011, 01:03 AM
Hi Guys, I just joined today and some of you are going to be happy about it! Your finally going to get some answers. My name is James, I'm from MB Canada, and I built the Baddest 350X anyone has seen in my area! I took my stock 350X added an L.A. Sleeve 425cc Bigbore kit $350 and $400 to get the cylinder machined to accept the sleeve, Extreme port & polish, shortened bronze valve guides and custom +2 oversize valves courtesy of Allen at C T Racing! ($1000.00) Also hardwelded rockers and R&D valve springs & Titanium Retainers. On top of that, a Webcams Race cam (40b), Powroll 6mm Stroker Crankshaft (making it 460cc's!), DG Excellerator exhaust,(JUST KEEPS GETTING BETTER & BETTER DON"T IT?) Topped off with TRX 450R Carb and K&N air filter! ...And I'm hungry for some 450's!!!

GeoD
02-09-2011, 02:03 AM
Hi 3Wheeler. Glad to have you on the boards. Your ride sounds like one bad azz wheeler!! Be sure to post some pics!! Have you had it out yet?

3Wheeler
02-09-2011, 10:26 AM
No, just have to build an adpter to make that 450r carb fit. I rode it this fall with a 400ex carb on this set up and had the chance to Race my buddys Kawi B F 750cc EFI. I WASTED him!! I told him I'm not going again till next spring. I'll get some pic's up this weekend. (thanks for the welcome)

3Wheeler
02-09-2011, 12:41 PM
This Is the Thunder God!

3Wheeler
02-14-2011, 11:07 AM
You could always try one of these! http://cgi.ebay.com/ebaymotors/Honda-ATC-350x-Big-Bore-kit-cylinder-banshee-250r-trx-_W0QQcmdZViewItemQQhashZitem19c3228555QQitemZ11064 8001877QQptZMotorsQ5fATVQ5fPartsQ5fAccessories

kt60016
02-14-2011, 11:19 AM
Ques. lol how do you stop that thing i only see the front brake don't see the rear brake foot pedal

blowyourmind
02-14-2011, 07:15 PM
hey i only got front brakes on my 200x and it stops ok. workin on gettin the rest of the parts for the rear. be carefull though if you aint got binders all around. its not the safest ride.

kt60016
02-14-2011, 07:31 PM
mine does till you are haul azz across gravel and hit it then it just slides so i stomp on the pedal which stops it faster :happy0144:

3Wheeler
02-14-2011, 09:17 PM
Ques. lol how do you stop that thing i only see the front brake don't see the rear brake foot pedal
Wow! You watch the details. If you look even closer ,there's no skid-pans or grab bar either! This Pic was taken after the local Drags. (gotta save weight you know.)

3Wheeler
02-22-2011, 12:40 PM
Check the Master Parts List.

There are several Big Bore Kit places listed. There's one that makes a 452cc kit. Im going to recommend a dual oil cooler if you go big bore.

Im guessing the 425cc kit will be able to beat the 450Rs since you won't have the extra tire and frame weight. Plus you won't have the radiator and coolant weight. Unfortunately, you might have a hard time keeping the front end down.

If you're really serious about a big bore kit and what it can do I would suggest contacting Mickey Dunlap from Four Stroke Tech or Bill from TPC Trikes and run the specs by them and see what they say and/or recommend. These guys have been racing and modifying trikes forever. Mickey was one of the OG's in wheeler racing.

Now, if you really want to beat the 450Rs you can always save up and buy a TPC Trike!! Its a 450R trike conversion. One of the baddest rides around!! Not to mention one of the nicest conversions ever designed.

http://www.tpctrikes.com
I have the 425 BB, webcams 214 grind, 400ex carb, supertrapp exhaust and I still couldn't get it done. Tried a raptor 660 too http://www.youtube.com/watch?v=Malr5hlMnhY

Malr5hlMnhY

dom
02-22-2011, 12:48 PM
Nice! Looks like you were pulling pretty hard though!

3Wheeler
02-22-2011, 02:55 PM
I was gaining on him at the 3/4 mark!

GeoD
02-22-2011, 07:39 PM
You didn't get the holeshot. That's why you lost. The guy won with the same lead he had off the line. Gotta get the holeshot dudeman!! Nice vid!

3Wheeler
02-22-2011, 08:06 PM
Thanks. I'm extending the swingarm 4" for this Years drags (that should keep the nose down). I'm practicing my Holeshot!

Unregistered
02-14-2012, 06:56 PM
whats the biggest bore i can go on a stock rod

3Wheeler
02-16-2012, 08:43 PM
whats the biggest bore i can go on a stock rod
$452cc's is as big as I've seen. I wouldn't go much bigger anyways as a stock head can only flow so much.