Uma Superhead Tips & Tricks

[recta igbaras]

Hi guys

If you just bought uma superhead here are the tips and tricks that you can do to your uma superhead and uma 62mm bore

First the unboxing

Now you have already the superhead, Is it plug and play?
Yes its plug and play together with the 62mm uma borekit for superhead.


However if you want more performance, its advisable to finely tune it.
which means you need to
-port matching & resurface the intake port
-polish the exhaust port

i dont want to call it port and polish due to it might be misunderstood.


PORT MATCHING
What i mean by port matching is you have to make sure that the intake manifold outlet side perfectly
match to the lip of the intake port. it should not block the air coming from the manifold.
View attachment 26845
you need to remove that excess material in the head so that the air flow will not be obstructed.


PORT RESURFACING
resurface the the wall of the intake port. Do not enlarge!
you just need to resurface it so that the roughness is equal.

View attachment 26848



KNIFE EDGE the DIVIDER in the intake port
yes that wall in the center that divides the air going to the left intake valve and right intake valve.
View attachment 26846
by default the front side is not knife edge which destroys the smooth flow of air. you have to make that
front surface as sharp as knife that will cut the air into two.




Mirror Polish the exhaust port if you can
make the exhaust port as shiny as possible like a mirror
that way the carbon deposits wont build up in the exhaust port
Do not enlarge! you just need to mirror finish it .

View attachment 26847
in here, the exhaust port is not yet mirror finished, it takes time and effort to do it.


VALVE SPRING
some users say the valvespring that is included in the uma superhead is too stiff!
when i compared both the included valvespring stiffness of the uma superhead and the cms valvespring
the uma vspring is much stiffer, so i decided to use the CMS valvespring since im satisfied with it
on high lift cams.

besides my target RPM is on 12,000 - 13,000rpm so i dont need a too stiff valvespring.
if you want higher rpm you can use the included uma valvespring.


JETTINGS:

I am using 26mm Yoshimura TM MJN carburetor.
before i install superhead, i use the ff jettings

bigvalves 18/22 jettings on MJN 26
-pilot jet #37.5
-mainjet #110

now after installing superhead, i found out that this jet are perfect
on yoshimura 26mm
-pilotjet #40
-mainjet #120

FOR TIPS ON YOUR UMA 62mm PISTON
visit this Top Secret Section
http://www.yamahat135.com/forums/top-secret-section.73/



Enjoy your superhead!

View attachment 26849

i cant open the top-secret-section.. can u pls help me sir traxxas..

 

[egbert123]

si @john_carlo even though for daily use or long rides on high rpm the stock conecting is safe to use?

 

[Carl Louie Capua]

Uma Superhead + 62mm Uma borekit = ? how much? I have already 28mm UMA carb. What else should i buy or change to come up with the perfect set? Please help on this... This is my birthday gift to myself

 

[john_carlo]

si @john_carlo even though for daily use or long rides on high rpm the stock conecting is safe to use?

It depends on what will you do to your set.. I'm using uma super head + uma bore shave, piston been lighten, lighten piston pin, 28mm uma carb long drive or daily use no problem till today...

 

[john_carlo]

Uma Superhead + 62mm Uma borekit = ? how much? I have already 28mm UMA carb. What else should i buy or change to come up with the perfect set? Please help on this... This is my birthday gift to myself

Prepare prepare 25000 for the uma set bore and head

 

[zcbitik]

pap's - does this kind of setup (straight UMA - head and block) is good for A/C? im still thinking if I will go straight UMA if the price diff of machineshop for the head and labor, plus uma cam, manifold, cms valve 19/22 is not to far on the price of the complete Super HEAD package

 

[john_carlo]

pap's - does this kind of setup (straight UMA - head and block) is good for A/C? im still thinking if I will go straight UMA if the price diff of machineshop for the head and labor, plus uma cam, manifold, cms valve 19/22 is not to far on the price of the complete Super HEAD package

I think its good also for me...

 

[egbert123]

very good information sir @john_carlo...i'm using rb rearset.. were unable to use kickstart on this set..are electric starter can still start the motor or theres an other option..

 

[john_carlo]

very good information sir @john_carlo...i'm using rb rearset.. were unable to use kickstart on this set..are electric starter can still start the motor or theres an other option..

Don't remove the decompression assembly.. I'm using uma starter motor coz stock started cannot start the engine also I'm using uma cam gear...

 

[zcbitik]

Don't remove the decompression assembly.. I'm using uma starter motor coz stock started cannot start the engine also I'm using uma cam gear...

pap's you use UMA starter motor, my question is does the stock starter cannot start this uma (head/block) setup? it is really necessary to upgrade the starter too?

 

[tabi1]

Prepare prepare 25000 for the uma set bore and head

Sir, is that 25K for everything necessary? Also, i am picking up a new Sniper MX Saturday. What about modifying a brand new engine, any issues or should some miles be put on the motor before upgrades be done? Can someone recommend someone in the Angeles City area good enough to do such work?

 

[zcbitik]

Sir, is that 25K for everything necessary? Also, i am picking up a new Sniper MX Saturday. What about modifying a brand new engine, any issues or should some miles be put on the motor before upgrades be done? Can someone recommend someone in the Angeles City area good enough to do such work?

@tabi1 - bro 25k is only rough draft for UMA Head and block, it might go higher or less depend on your resource(seller) you also need RCDI, clutch spring and upgrade your exhaust(pipe), well I forgot the most important,, your trusted mechanic, I know I read it here that the UMA is match with Leo Vince pipe, or better buy a pipe suit for this setup like yoshimura or AHM , and if I am not mistaken if stock starter cannot do E-Start you also need to upgrade to UMA starter or same specs as this starter (gurus please correct me if I am wrong)

for a brandnew engine, why not use it for the meantime enjoy your stock engine, after a few months if warranty is not an option and not satisfied with the speed then decide if you really want to upgrade ...

 

[tabi1]

@tabi1 - bro 25k is only rough draft for UMA Head and block, it might go higher or less depend on your resource(seller) you also need RCDI, clutch spring and upgrade your exhaust(pipe), well I forgot the most important,, your trusted mechanic, I know I read it here that the UMA is match with Leo Vince pipe, or better buy a pipe suit for this setup like yoshimura or AHM , and if I am not mistaken if stock starter cannot do E-Start you also need to upgrade to UMA starter or same specs as this starter (gurus please correct me if I am wrong)



for a brandnew engine, why not use it for the meantime enjoy your stock engine, after a few months if warranty is not an option and not satisfied with the speed then decide if you really want to upgrade ...

zcbitik - Thanks and I know what your saying about it being new but I am not stressing on the warranty. I have ridden 1000cc bikes and up for 30 plus years so going to something under 100HP is a big adjustment to me so I am fully psyched to see this bike to have the stock HP doubled!! My girl picks up the bike Friday and I wont be home for about a month so it will have a few miles on it by the time I get there, lol.

 

[Carl Louie Capua]

@tabi1 - bro 25k is only rough draft for UMA Head and block, it might go higher or less depend on your resource(seller) you also need RCDI, clutch spring and upgrade your exhaust(pipe), well I forgot the most important,, your trusted mechanic, I know I read it here that the UMA is match with Leo Vince pipe, or better buy a pipe suit for this setup like yoshimura or AHM , and if I am not mistaken if stock starter cannot do E-Start you also need to upgrade to UMA starter or same specs as this starter (gurus please correct me if I am wrong)

for a brandnew engine, why not use it for the meantime enjoy your stock engine, after a few months if warranty is not an option and not satisfied with the speed then decide if you really want to upgrade ...

With the complete set of UMA, is it really won't work with kick starter? I mean, cannot kick the kick starter?

 

[john_carlo]

Use the decomp assembly for the stock starter motor

 

[traxxas-modifier]

With the complete set of UMA, is it really won't work with kick starter? I mean, cannot kick the kick starter?

estarter will work

 

[RockRobin]

may i ask, what is the final review (dynorun etc) of the Uma superhead? thank you

Hi guys

If you just bought uma superhead here are the tips and tricks that you can do to your uma superhead and uma 62mm bore

First the unboxing

Now you have already the superhead, Is it plug and play?
Yes its plug and play together with the 62mm uma borekit for superhead.


However if you want more performance, its advisable to finely tune it.
which means you need to
-port matching & resurface the intake port
-polish the exhaust port

i dont want to call it port and polish due to it might be misunderstood.


PORT MATCHING
What i mean by port matching is you have to make sure that the intake manifold outlet side perfectly
match to the lip of the intake port. it should not block the air coming from the manifold.
View attachment 26845
you need to remove that excess material in the head so that the air flow will not be obstructed.


PORT RESURFACING
resurface the the wall of the intake port. Do not enlarge!
you just need to resurface it so that the roughness is equal.

View attachment 26848



KNIFE EDGE the DIVIDER in the intake port
yes that wall in the center that divides the air going to the left intake valve and right intake valve.
View attachment 26846
by default the front side is not knife edge which destroys the smooth flow of air. you have to make that
front surface as sharp as knife that will cut the air into two.




Mirror Polish the exhaust port if you can
make the exhaust port as shiny as possible like a mirror
that way the carbon deposits wont build up in the exhaust port
Do not enlarge! you just need to mirror finish it .

View attachment 26847
in here, the exhaust port is not yet mirror finished, it takes time and effort to do it.


VALVE SPRING
some users say the valvespring that is included in the uma superhead is too stiff!
when i compared both the included valvespring stiffness of the uma superhead and the cms valvespring
the uma vspring is much stiffer, so i decided to use the CMS valvespring since im satisfied with it
on high lift cams.

besides my target RPM is on 12,000 - 13,000rpm so i dont need a too stiff valvespring.
if you want higher rpm you can use the included uma valvespring.


JETTINGS:

I am using 26mm Yoshimura TM MJN carburetor.
before i install superhead, i use the ff jettings

bigvalves 18/22 jettings on MJN 26
-pilot jet #37.5
-mainjet #110

now after installing superhead, i found out that this jet are perfect
on yoshimura 26mm
-pilotjet #40
-mainjet #120

FOR TIPS ON YOUR UMA 62mm PISTON
visit this Top Secret Section
http://www.yamahat135.com/forums/top-secret-section.73/



Enjoy your superhead!

View attachment 26849

 

[RockRobin]

i am going to buy one. but i would like to use TZM carb. is it possible ? what is the mainjet & pilot jet setting for tzm carb + superhead + 62mm UMA? what tappet setup for in & ex?

 

[tabi1]

may i ask, what is the final review (dynorun etc) of the Uma superhead? thank you

I would like to see the dyno on it too. I had it installed last week on my fiancee's bike and even without CDI or the UMA 32mm adjusted it was a beast. The CDI and carb is now in and adjusted but i am not home to ride it but i hear it's even more amazingly strong and smooth. Very pleased with the non adjusted version already, so with the CDI and carb tweeks i know i will be opening the beast up a lot more.

 

[RockRobin]

I would like to see the dyno on it too. I had it installed last week on my fiancee's bike and even without CDI or the UMA 32mm adjusted it was a beast. The CDI and carb is now in and adjusted but i am not home to ride it but i hear it's even more amazingly strong and smooth. Very pleased with the non adjusted version already, so with the CDI and carb tweeks i know i will be opening the beast up a lot more.

Do you mean even with the standard carb and CDI the superhead setup is already a mad cow? I am really looking foward to my superhead ^_^