piaggio zip cat 50 ac, q-tre pipe, what jet and rollers?

Discussion in 'General Tuning' started by wayne678754654, Oct 28, 2016.

  1. wayne678754654

    wayne678754654 New Member

    Messages:
    5
    hi guys I need some pro advice, I got a zip 50 cat. standard airbox, standard cylinder, with a tecnigas q-tre pipe what jet and rollers I need? done a lot of research and found conflicting sizes/weights...
    anyone here actually know what they're talking about? :)
     
  2. Tamiyacowboy

    Tamiyacowboy Pippa's Owner

    Messages:
    1,850
    Rides:
    Piaggio Skipper
    depends what you have in already as a main jet size, but i would have thought around 66 - 68.

    rollers depends on the rider, if you want some bite low down and keep revs up high you tend to go to around 6g on the rollers , maybe a set of 5g if your not happy with the take off.

    Carb jetting is for the motor to make sure its happy and not going to smoke itself with a heat seize or end up staved of fuel once your running up.

    roller tuning is the rider side, what they want from the get up and go, ie bite like a tiger and fly off the line. BUT there is a draw side, the lower the weights you use the less that variator face is going to get pushed out so its a balance between your take off and outright top end speed. you cannot have both but you can have a half way ie not so bad take off pull and atleats some still good top end
     
  3. wayne678754654

    wayne678754654 New Member

    Messages:
    5
    cheers for the reply im currently running a 66 in there and I took the plug out to see what colour it was after giving it some on the stand but it was a bit on the black side, also when I took it out I noticed smoke coming out of the barrel is that normal? with the standard air box the hole the air gets sucked in through is very small.
     
  4. Tamiyacowboy

    Tamiyacowboy Pippa's Owner

    Messages:
    1,850
    Rides:
    Piaggio Skipper
    we tend to do a plug chop with a brand new plug. an old one can give you a false reading.
    adding an open airfilter will cause more problems meaning up jetting even more as the motor then gets huge amounts of air and less fuel.

    some airboxes have a small restiction tube inside them leading from the main inlet pipe to the airbox itself , some have a little plug inside the main airbox tube lading to the foam filter with a few holes in. these can be removed but you would need to adjust carb to suit. ie re-jet up another size and/or adjust idle side of settings.

    if motors just been running hard and your taking out the plug right after you can have a little waft of smoke come from the piston head , if the piston is sitting mid way in the barrel both the exhaust and fuel ports will be opened and smoke left in the exhaust will try and escape through those open ports and out the top of the head.
     
  5. wayne678754654

    wayne678754654 New Member

    Messages:
    5
    I took it for a ride yesterday with the 66 jet and needle set in middle with 4.8g rollers, at wot I had to back off a bit for more power, this mean main jet too small? bike was revving high but didn't pick up much speed, rollers too light?
    glad to know the smoking is ok then :) and yeh im not gonna bother with an open air filter, the belt is on the wear limit also (17.5mm)
    oh and when I installed that 66 jet it would only tick over with the tickover screwed all the way in, that's not right is it? I got air screw 1 1/2 turns out, I thought pilot might be blocked but checked and it wasn't.
    reason I used those 4.8g rollers was because I phoned a guy at pedparts after finding this http://www.pedparts.co.uk/blog/tecnigas-exhaust and thought he would know the set up, and he told me to use them with a 68 jet but the guy at the shop only had 66.
     
    Last edited: Oct 30, 2016
  6. wayne678754654

    wayne678754654 New Member

    Messages:
    5
    tried a 68 in there today and I don't get more power if I back of throttle a bit and the plug looks about right, light brownish color but the top speed is dead as hell. gonna try the 7 grams I got in there later hopefully it picks up more speed. could the belt being on the limit (17.5mm wide) somehow limit top speed?
     
  7. MiNoR cOnFuSiOn

    MiNoR cOnFuSiOn Administrator Staff Member

    Messages:
    14,276
    Rides:
    et2 monster
    a thinner belt will lower the gearing potential, you will feel it rev out tho. so get to the top of the gearing and then the revs rise and rise.. 66 sounds about right on a 17.5mm carb on a piaggio engine, anything from 5g to 7g is usually about the ballpark for a pipe, its a case of buying a few sets and seing, ive not used these pipes so can only assume, again the majorioty of piaggio pipes made for 50 cylinders (so the word sport) run around 5.5g rollers, as they dont make any more power, just move it around a bit and most sport pipes hit power at around 7800 to 8400rpm... go up on the rollers, alternate them with the original (so 3 and 3) and you will gain a little weight. good for experimentation. if you use more than one weight then you need to work out the avarage weight. so add the weights devided by the number of diff weights.. so 3 6.5g rollers and 3 4.2g rollers i would add the two diff weights together then devide by how many diff weights. so 10.7 = 5.35g.. can do this with 3 pairs of diff rollers.. just be sure there even, so if using 3 pairs they sit OPPOSIT each other in pairs, if using 2 diff weights of 3 rollers each, they go heavy light heavy light heavy light as you install them. over explaining something fairly simple tbh. the bike will tell you whats up, order a few sets and have a play
     
  8. Tamiyacowboy

    Tamiyacowboy Pippa's Owner

    Messages:
    1,850
    Rides:
    Piaggio Skipper
    revs dropping out.

    your pipe is made to produce peak horse power at a certain rpm range spread, so the TG Q-tre is about 7.400 rpm to around 8.400rpm.
    lets say at 7.4k rpm your bikes producing 5hp at 7.9k its producing 5.9hp and at 8.4k is droped back to 5hp. so ideal area is getting that variator to hold the rpm at 7900rpm thats a very defined rpm and is going to be very hard to nail it perfect.
    a sports pipe like a q-tre will have a nice wide'ish rpm spread so if a newbie tuner was to say put slightly to heavy or light weights in it wouldnt matter to much as that wide rpm spread can cope.

    A highly tuned race pipe will have an even more narrow rpm band like 9000rpm to 9300rpm so you have a very narrow 300rpm band to fit into with this coupled with a say high end 70cc race cylinder setup your powerband could be 9hp but because of the very narrow powerband spread its going to be even more harder to tune the variator for this rpm range

    Now beyond 8400 rpm the pipe is starting to fall out of its powerband range where it and the engine produces its peak horsepower, to gain more speed the rpm has to raise higher by a factor of around 7-15% , think of this power curve like a hump on a graph the top of the hump is peak HP , but beyond that it starts to slope away and the hp starts to lower by 9000rpm the horsepower has dropped to 4.5hp because the motor is maxed out on its fixed gearing and cannot keep the powerband.
    rollers are like a rpm holder in the variator. a lighter roller means your variator will hold a higher rpm , you tend to tune a roller weight to keep at a certain rpm and that rmp your aiming for is where the pipe and engine produces its max HP.

    Thats where Minor confusions roller tuning comes in trying differnet weights to find the sweet spot where the pipe produces the max hp at a given rpm and the rollers are key to this.

    the reason your rpm falls off at wot is because you have exceeded the max rpm of the given max hp output, you climbed up the hump got to the top and instead of holding at the top started to roll down the other side
     
    Last edited: Nov 17, 2016
  9. Tamiyacowboy

    Tamiyacowboy Pippa's Owner

    Messages:
    1,850
    Rides:
    Piaggio Skipper
    revs dropping out.

    your pipe is made to produce peak horse power at a certain rpm range spread, so the TG Q-tre is about 7.400 rpm to around 8.400rpm.
    lets say at 7.4k rpm your bikes producing 5hp at 7.9k its producing 5.9hp and at 8.4k is droped back to 5hp. so ideal area is getting that variator to hold the rpm at 7900rpm thats a very defined rpm and is going to be very hard to nail it perfect.
    a sports pipe like a q-tre will have a nice wide'ish rpm spread so if a newbie tuner was to say put slightly to heavy or light weights in it wouldnt matter to much as that wide rpm spread can cope.

    Now beyond 8400 rpm the pipe is starting to fall out of its powerband range where it and the engine produces its peak horsepower, to gain more speed the rpm has to raise higher by a factor of around 7-15% , think of this power curve like a hump on a graph the top of the hump is peak HP , but beyond that it starts to slope away and the hp starts to lower by 9000rpm the horsepower has dropped to 4.5hp because the motor is maxed out on its fixed gearing and cannot keep the powerband.
    rollers are like a rpm holder in the variator. a lighter roller means your variator will hold a higher rpm , you tend to tune a roller weight to keep at a certain rpm and that rmp your aiming for is where the pipe and engine produces its max HP.

    Thats where Minor confusions roller tuning comes in trying differnet weights to find the sweet spot where the pipe produces the max hp at a given rpm and the rollers are key to this.

    the reason your rpm falls off at wot is because you have exceeded the max rpm of the given max hp output, you climbed up the hump got to the top and instead of holding at the top started to roll down the other side
     

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