i want to do some performance upgrades for cheap is there any thing i could do to the motor for cheap that would up the power or any other things like exhaust mods. and whats the best cdi jaguar 
best performance upgrade on a budget
- Thread starter Hoopermotorbikes
- Start date
the cdi should be last on your list. i get my bike up to 40 on the regular with the stock cdi and i have had no issues what so ever with it though i am shure the jag or HD lightning will increase spark substantialy you wont need it untill you got a high comp motor and a freed up exhaust.i want to do some performance upgrades for cheap is there any thing i could do to the motor for cheap that would up the power or any other things like exhaust mods. and whats the best cdi jaguar
first mods should be port and polish and a good port match, this will make your motor rev quicker and rev higher and porduce more power, how mutch power ? eehhh well enough to notice a differance but dont expect a lot with only that as a mod.
second i would ether deck your stock head all the way down to the fins ! take the gasket surface down as far as you can, there should be a fingernail lip for a gasket surface. the stock comp is 6:1 and going with 12:1 doubles it and will help make power all across the rpm range, i etamate a 5% increase in power at 12:1 comp. not mutch but hey every little mod adds up in the end .
you can buy a puch head ... the 70cc hi hi is quite nice and the fred head is top of the line ! also there is the manic mechanic head and a few others
now that your motor is ported and running higher comp you need to buy or make a sweet x chamber exhaust and tune the header length. or you can mod your stock exhaust by cutting it open at the first weld and gutting all the catalitic converter parts and sutch, then drill out the stinger pipe to 1/2 inch or bigger i like 5/8ths. if you want an easy custom exhaust you can make a strait pipe, be shure to use 1 in aluminum tubing and make it TOO LONG ! this way you can ride it and then cut one inch off at a time untill the length is tunned to the rpm you ride at most . this does work contrary to belief and will give you a power band albeit a short band but it will be powerfull where your bands rpm range is .
next is piston mods ... cut the skirt so it does not block the intake at TDC, then if you wish you can grind ramps in the dome to add duration to the transfer ports and exhaust port. also you can lighten up the top end with a titanium wrist pin.
now that you have more power and rev's you have to focus on your gearing ! a shift kit would be ideal but not all of us have 250$ to toss at a HD shift kit ! so you can go with a 40T rear sprocket and gain some speed with out sacrafising torque, you have more HP now so the smaller sprocket wont take away to mutch torque as compared to stock, in fact you may have even more power than stock now even with the smaller sprocket ! if its all out speed u want go with a 36 or 32 t rear but be warned you wont be climbing any big hills though you shure will be fast !
on to the bike itself ! all the power in the world is no good unless you can stop ! you need good breaks ! also rebuild your hubs with good auto grease so they have less rolling resistance and get a good set of tires like maxis hookworms or a clone of that type of tire.
and thats all i can think of now ... keep your carb tunned and properly jewtted also use an NKG plug iridium is best
you dont realy need a bigger carb than stock 15 or 16mm is fine i personaly love the CNS V1 carb and the dellorto sha is great also .
-the cns V1 its a great carb ! if you know how to tune it ! 16mm and fully tunable
-best carbs for the money would be a used cns v1 people do not know how to tune them and they get rid of them for a dellorto sha.
-the dellorto sha yeh its only 15mm but its easy to tune using only one jet and it atomizes fuel realy well so it offers preformance over the stock nt
- the dellorto phbg 16 17 18 19 mm carbs , thease are fullt tunable carbs that require a good mechanic to dial in but they offer unsurpassed preformance !
-the dellorto 16.16mm sha its a 16.16mm version of the sha its an original and there are NO clones of the 16.16 so you will have to dish out 60$ for it but its worth it if you need a better flowing carb for a monster motor and you cant tune a carb !
- the mikuni vm 18mm this is the top of the line mikuni carb for the china girl best preformance you can get for reasonable money !!! expect to spend all week tunning it lol
- other carbs will work too but the ones listed are the normal for the china girl i have seen al the way up to 28mm on thease motors !
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on a low and tight budget .....
puch head 70cc hi hi 40$
port and polish 0$
port match 0$
modded exhaust 0$ or strait pipe tuned length 10$
used cns v1 carb or dellorto sha clone 30$
40 t rear 15$
65$ there you go !
puch head 70cc hi hi 40$
port and polish 0$
port match 0$
modded exhaust 0$ or strait pipe tuned length 10$
used cns v1 carb or dellorto sha clone 30$
40 t rear 15$
65$ there you go !
On a two stroke, the best mod for the money is an exhaust expansion chamber. You can also do the port matching and cleanup yourself with a Dremel. On a four stroke, I would spend the money elsewhere. Hopping up a four stroke is more expensive and not so DIY.
Thank you for all your response but I don't have access to a mill but I do have a drill press and is there a way to sand down the to add compression to the stock and how far would I have to go ? And once again thank you 
Welcome to the forum.i want to do some performance upgrades for cheap is there any thing i could do to the motor for cheap that would up the power or any other things like exhaust mods. and whats the best cdi jaguar
We don't know exactly what bike or motor you have so kinda hard to give advice.
I presume you have some kind of China girl since you mention that jaguar CDI
Do you ride up hills in Ojai?
What kind of skill level do you have mechanically?
Is your bike a commuter or a fun toy?
thats right what motor is this ?? if its a preditor 79 or 99 or bigger you got some money to spend !!! lol
you need to pull the case open and remove the entire govener syst and then install an aluminum fly wheel for higher rpms, then you need to modify the valve train to handle the rpms by installing a larger lobe cam and tighter valve springs to prevent float, you can also go with longer ratio roller rockers or stampped ones for even more lift without having to add duration to the camshaft! then deck down the head for higher comp , then you can even do a 3 or 5 angle valve job and lap them if you own valve cutting tools... i bought a set for 5 mm valve guids for 150$ 5mm is the standard hjonda gx 160 and clone size, that was a bonuse i realy bought it for restoring 3 wheelers ! it would seem 5mm is a verry standard size valve guide ! then make a tottaly free floing exhaust for high rpms or get a SUPERTRAP tunnable backpreasure exhaust ! the suppertrap is ALL i recomend for any four stroke build atv or dirt bike even karts because the header tubes are large and free flowing and the exhaust end has a series of plates that you stack together to make your own back preasure, more plates = less back preasure, less plates = more back preasure and you can fine tune it further with the end plat wich can be flat leaving only the plates for the gasss to escape from or you can add a plate with any size hpole you want to relieve the gasses escaping from the tunned plates ! the supper trap is by far the best 4 stroke exhaust on the market simply caust it has near infanite tunnability !... people say ohhh well i like my FMF Fatty cause it has this back preasure or it does that lol well i can tune my supper trpp to make the exact same back preasure !!
thye second pic is the one i runn on all my resotored and modded honda atc 3 wheelers ! i add 3 more plates and a 1in hole end cap for racing setups but the stock 16plates and flat cap work well for dirt and trail riding the last pic is that of the disk pack
its called supper trapp because the series of plates trap a given amount of gasses to creat back preasure and you tune the trapped gasses and preasure by adding or removing plates and changing end caps. this mod allone on a 4 stroke will give you the abillity to tune your motors power at a given rpm at any time with only a single alen wrench and a few min of your time ! fair warning though .... this exhaust syst gets louder and louder the more plates you add ! its quieter than the stock honda exhaust on my 3 wheeler with 12plates and a closed end cap but with 22 plates and a 1in hole forget it lol it sounds like a harley !
you need to pull the case open and remove the entire govener syst and then install an aluminum fly wheel for higher rpms, then you need to modify the valve train to handle the rpms by installing a larger lobe cam and tighter valve springs to prevent float, you can also go with longer ratio roller rockers or stampped ones for even more lift without having to add duration to the camshaft! then deck down the head for higher comp , then you can even do a 3 or 5 angle valve job and lap them if you own valve cutting tools... i bought a set for 5 mm valve guids for 150$ 5mm is the standard hjonda gx 160 and clone size, that was a bonuse i realy bought it for restoring 3 wheelers ! it would seem 5mm is a verry standard size valve guide ! then make a tottaly free floing exhaust for high rpms or get a SUPERTRAP tunnable backpreasure exhaust ! the suppertrap is ALL i recomend for any four stroke build atv or dirt bike even karts because the header tubes are large and free flowing and the exhaust end has a series of plates that you stack together to make your own back preasure, more plates = less back preasure, less plates = more back preasure and you can fine tune it further with the end plat wich can be flat leaving only the plates for the gasss to escape from or you can add a plate with any size hpole you want to relieve the gasses escaping from the tunned plates ! the supper trap is by far the best 4 stroke exhaust on the market simply caust it has near infanite tunnability !... people say ohhh well i like my FMF Fatty cause it has this back preasure or it does that lol well i can tune my supper trpp to make the exact same back preasure !!
thye second pic is the one i runn on all my resotored and modded honda atc 3 wheelers ! i add 3 more plates and a 1in hole end cap for racing setups but the stock 16plates and flat cap work well for dirt and trail riding the last pic is that of the disk pack
its called supper trapp because the series of plates trap a given amount of gasses to creat back preasure and you tune the trapped gasses and preasure by adding or removing plates and changing end caps. this mod allone on a 4 stroke will give you the abillity to tune your motors power at a given rpm at any time with only a single alen wrench and a few min of your time ! fair warning though .... this exhaust syst gets louder and louder the more plates you add ! its quieter than the stock honda exhaust on my 3 wheeler with 12plates and a closed end cap but with 22 plates and a 1in hole forget it lol it sounds like a harley !
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If I read the title of this thread right I believe the OP asked for information about what he could do "on a budget".
Suggesting major modifications to a new engine to someone who apparently doesn't want to spend mega dollars is a waste of time and may deter him from going forward with his project. Keep the questionable advice for major modifications for the high performance section. Leave the new builder to learn the basics first.
Tom
Suggesting major modifications to a new engine to someone who apparently doesn't want to spend mega dollars is a waste of time and may deter him from going forward with his project. Keep the questionable advice for major modifications for the high performance section. Leave the new builder to learn the basics first.
Tom
If you've got a 2 stroke China Girl, the cheapest upgrade that will give you noticeable increases will be an automotive type plug wire and an upgraded spark plug. You're look'n at about $12 max depending on the spark plug you choose.
Good luck with your progress!!
Good luck with your progress!!
thanks guy i have the 49 cc sky hawk motor i think it 49 cc because it more round and smaller than the 80 cc motor i cant post a pic because i don't have a camera that would mach the specifications for the web. and guys i am looking for the little things like sanding down the head or matching ports not super charging a moped. but i would like to use get the nitrous kit. does any one have any experience with nitrous. and we do have hills in ojai
[QUOTE="Hoopermotorbikes] sanding down the head or matching ports not super charging a moped. but i would like to use get the nitrous kit. does any one have any experience with nitrous. and we do have hills in ojai[/QUOTE]
Nitrous kits for these motors are a bad joke and a total waste of your money.
How much is a nitrous kit?
An expansion chamber should be your first upgrade if you decide a 48cc is even worth dumping much money into.
[/QUOTE]Nitrous kits for these motors are a bad joke and a total waste of your money.
How much is a nitrous kit?
An expansion chamber should be your first upgrade if you decide a 48cc is even worth dumping much money into.
Come on guys. Roger just gets a little excited about porting and stuff most of us don't understand.
Gotta love the enthusiasm.
*hides the dremel*
Gotta love the enthusiasm.
*hides the dremel*
lol ...... i am also aflicted with severe adhd and am always over exited so when i actualy get exited..... lol
the only reason i ever got into motors was because i needed something to do with my hands to keep me out of trouble... at 12 years old you have no idea how many motors were destroyed by me pulling them compleatly appart right down to every last nut and bolt and not knowing how they go back together lol that is how i learned. i would strip my moms lawn mower down to nothing oblivious of the consiquenses and upcoming punishment but its from those experiances at sutch a young age that i learned about motors, by 13 years old i had modified a 70cc demo saw i found in the trash to run the balls and welded a mount on the seat tube of my haro bmx bike to mount it ! that was my first build at 13 years old and i dont think i have built a faster motorized bicycle yet LOL !!! that thing was suicide to ride ! it got confiscated when i was 14 by the police i got pulled over for SPEEDING !!!! in a 30 mile an hour zone !!!! i was told i was going over 50 and then the cop proceded to call me all kinds of stupid names and told me how dumb i was for going so fast on a pedal bike at my age with no helmat. MY dad laughed my mom grounded me
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Roger I know the feeling the cops could not catch my first build that I started at 12 but it was a 60s something VW rail job that I built more times then I care to remember just because my dad would bring home a new rebuild kit with bigger jugs ect every few weeks. had 2 cops try to catch me when I was 14 on a curvy road one day both of them ended up in a big ditch. My dad heard the whole thing on a scanner and 3 days later my rail job was sold for almost nothing lol
