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Discussion Starter · #1 ·
I have been interested in pocketbikes for a long time but just picked one up this week. I work on cars at work but have no experience with 2 strokes and very very little with carbs. That is one reason I wanted a cag, besides loving small vehicles.

Here is the newest addition next to my daily ride in the garage. As far as I can tell it is an MTA2 but it has a sidekick on the swingarm. I later moved it inside so I can mess with it on my coffee table while I watch TV.

As with all my vehicles I plan on having fun modifying it. It does have the separated cooling fins on the head indicating the 44mm bore but I haven't torn it apart yet to measure it out.

I want to get a larger carb, exhaust, and reed kit to start with, but am seeing different opinions about these things. I hear about people simply porting the stock carb and intake manifold, but I have also seen where the stock carbs use irregularly sized jets. I live more than 5000ft above sea level.

I have been looking at a Walbro WT-603 and was close to pulling the trigger but then read (on a non-pocketbike forum) that that particular carb was designed for piston port engines, not reed ones like the cag. They implied it would not run correctly on a reed engine. Is there truth to that? I also see many people recommending a Dellorto 14/14, but cannot find anyone selling those for the life of me.

Thanks in advance for the help, I look forward to lots of enjoyment out of this little thing.

-Matt
 

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Welcome to the site ...I have plenty of those kind of bikes,,,,mostly all of them are modded way past being stock now....If youd like you can check out my thread on the subject to get an idea how far these little things are capable of going......Theres plenty of other skilled members aswell

http://www.pocketbikeplanet.com/showthread.php?t=60828

Just know that your bike is a newer model therefore more extensive mods are going to be needed to even match the speeds of the older bikes................On the placard on the side does it say 43cc or 49cc.......?

The carb is non-adjustable ,,,the expansion chamber has a catalystic honeycomb blockage,,,the throttle has a restrictor screw,,the metal gastank is bogus and tends to crack where the plastic melds to the metal..

If your handy with a dremel you can juice that engine up to 3x its current power..........If not getting ahold of boosted306[sam]will get ya some pretty serious power................Good Luck with it







 

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Discussion Starter · #5 ·
Thanks for that link Cam2, I have actually been reading through your thread this last week and it is very informative. I still have 40 pages or so to go though.

Its a shame that it will take some extra work to get my bike up to speed with the older ones, but half the fun of something like this is working on and modifying it anyway.

My new bike's placard says 43cc. Is it actually 43cc then, or is it "43cc" like the old ones are "47cc" even though they aren't?
 

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Since your at 5,000 ft a Walbro might be your best choice, and cold and hot, have to kept re-jetting all the time, an Walbros have low & high screws on the side. I have a WT-603 on my avatar Custom Lucky 7 with a 5 port Cag engine I built from a kit and parts.
When you first put them on the throttle cable hook up can be a Pain, but no leaky or clogged turn off valve, no float needle or bowl to leak, easy to adjust. You need an aluminum manifold and you can put a fitting for a boost bottle before you put it on.
 

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Discussion Starter · #7 ·
Thanks EPR, looks like that would be a good choice for me then.

I read through your thread about boost bottles and it seems easy enough, as long as I get a correctly sized bottle and tap in the correct spot on the manifold. How much difference does the bottle make? I read somewhere they work better on piston-port engines than reed engines.

Is the throttle cable fitting issue just because of placement? I saw on one of the sites a replacement throttle cable bracket specifically for using WT carbs on cags, but wasn't sure if that's what it was for.
 

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Thanks for that link Cam2, I have actually been reading through your thread this last week and it is very informative. I still have 40 pages or so to go though.

Its a shame that it will take some extra work to get my bike up to speed with the older ones, but half the fun of something like this is working on and modifying it anyway.

My new bike's placard says 43cc. Is it actually 43cc then, or is it "43cc" like the old ones are "47cc" even though they aren't?
back in the day cags were classified 39cc and 47cc to get them through customs faster......Theyre true identity is now being shed to light because the chinese got caught playing a game of slight of hand..........

The fun does come from working on these things but the real fun comes from riding them and not dwelling on the way it runs either.......Good Luck on making your bike an enjoyably powerful and trouble-free as possible rider............:thumbsup:
 

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Thanks EPR, looks like that would be a good choice for me then.

I read through your thread about boost bottles and it seems easy enough, as long as I get a correctly sized bottle and tap in the correct spot on the manifold. How much difference does the bottle make? I read somewhere they work better on piston-port engines than reed engines.

Is the throttle cable fitting issue just because of placement? I saw on one of the sites a replacement throttle cable bracket specifically for using WT carbs on cags, but wasn't sure if that's what it was for.
Ive had no trouble fitting my walbros to my cags.......My retrofit kits come with two types of cable brackets but if its the one it can easily be bent and modded to clear the pullstarter housing



 

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Discussion Starter · #10 ·
So moving on to exhaust, I do not like that catalyst your picture above is showing. I have seen a lot of people praising the fatty exhaust, I guess from one of the cruisers, but it requires a fuel tank swap as well. Is it worth it or are there better options out there? Since you said the fuel tank cracking is a common issue I'm thinking I could kill two birds with one stone here.
 

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So moving on to exhaust, I do not like that catalyst your picture above is showing. I have seen a lot of people praising the fatty exhaust, I guess from one of the cruisers, but it requires a fuel tank swap as well. Is it worth it or are there better options out there? Since you said the fuel tank cracking is a common issue I'm thinking I could kill two birds with one stone here.
The JetPro is a good exhaust........Its gonna have to be seakled up really good though...I set mine and then welded it up totally sealed for life.........





Your gonna need a fueltank like this one........

 

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SDScooters, Hugh, in Texas is getting some new Mta2 full bodied Cags, with a 49cc Zen/Mitsu piston port engine. Believe they will be $320 shipped, that's good deal at todays prices. No more $169 A1 Cags, EPA and there smog crap ended that for Good.
 

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Discussion Starter · #14 ·
I don't understand why the EPA has any say on things that are not allowed on public roads anyway, they ruin everything. Why did they move from reed engines to piston port? I haven't torn my engine down yet, I hope it still has a reed, I have a new one on the way with my carb and exhaust.

I grabbed mine off craigslist, talked him down to 100 since it was missing footpegs and wouldn't hold an idle by itself. All the other cags locally are going for 200+.

My big bag of parts is on schedule to get here Saturday, just in time for the 3 day weekend. I will post an update once the stuff is on.

I read through a bunch of stuff on boost bottles. What are you using for yours EPR?
 

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I

I want to get a larger carb, exhaust, and reed kit to start with, but am seeing different opinions about these things. I hear about people simply porting the stock carb and intake manifold, but I have also seen where the stock carbs use irregularly sized jets. I live more than 5000ft above sea level.

I have been looking at a Walbro WT-603 and was close to pulling the trigger but then read (on a non-pocketbike forum) that that particular carb was designed for piston port engines, not reed ones like the cag. They implied it would not run correctly on a reed engine. Is there truth to that? I also see many people recommending a Dellorto 14/14, but cannot find anyone selling those for the life of me.

Thanks in advance for the help, I look forward to lots of enjoyment out of this little thing.

-Matt


Yes theres conflicting threads on the subject of carbs...........Its true that the piston ported engines come with pumper carbs but there are pocket quads and pocket dirtbikes come with pumper carb setups......

Ive run the gauntlet with these carbs...first I modded the crap out of the stock carb but time after time i ran into unexplained float hangups and have had quite a few tankfuls leaking all over the floor......The other thing that sucked was one day it ran killer the next like crap,,,after tuning it in by jetting it correctly and setting the c-clip right the next day it would run like crap which had me tearing into the carb again to get it running better....That was a big loss in fun.....

then I moved onto the 14/14 carb...it gave the engine way more pep but again I got the day by day running good or like crap tuning blues..without jets on hand and a journal to enter the info you can get lost whick kills the time for fun..................

Ive tried the 19mm deltoro carb and its a pain in the keester to get dialed in and I was using it on a 5 port cag........

After all the hooey I decided to give the pumper carbs a whirl seeings thats what Ive been running on my outlaw 133mph racekart back in the 80s........Ive never looked at any other carb again,....My cags are easy to start-up,,easy to tune and run so much better and cleaner with a dual circuit carb............I have pumper carbs on all my reeded engines and never been happier..........

Theres many-many different pumper carbs to custom tailor your engines powerband ,,,,,,







 
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