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so do you get a lot more power by ONLY taking off the extra pipe on the downpipe and welding over?
 

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2 Strokes And I'm Happy
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no. you need to do everything in one go.
 

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Firstly, Hi All!!
I race a '94 Mito Evo in the Post Classic series in Sydney, Australia. With no engine mods, a Jolly Moto pipe,and a 35mm Keihin PWK Carby, she puts out 31hp. I've recently put Boysen reeds in, but haven't had it back to the dyno yet. So, a couple of questions..
I've read on a Portuguese website that they're getting 50ish Hp from their bike. They've got a 41mm PWK carb, and a Gianelli pipe, but apart from that, it would be hard to guess what else they've done, Porting, running Methanol, etc. I'm also unsure of whether that 50HP is at the crank or back wheel. If it's at the wheel, I'm all ears!! Anyone else had these sort of figures from a Mito engine??, Is 41mm going to breathe easier, or will it drown the standard engine? Does anyone have any feedback on the Mitaka barrel and piston kits? would it be more beneficial to go to the later model head with the domed piston? (I'm currently using the standard flat top pistons)

Thanks in advance for your help.

Chuck
 

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2 Strokes And I'm Happy
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no way are they geting 50bhp form anywhere. mitaka a sh*t, use all cagiva parts.
 

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no way are they geting 50bhp form anywhere. mitaka a sh*t, use all cagiva parts.
Ok, straight to the point, No BS! Thanks.
Why is Mitaka sh*t? Do they have a history of failing? Or do they just not perform as well?
Can anyone shed some light as to whether Flat top pistons perform better than Domed?

Anything constructive, that will increase my current 31 Hp would be appreciated
 

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If the flat top is matched to the correct head it shouldn't make much difference when compared to a domed matched with a dome head.

Start a thread in the main mito section and you'll get more answers.
 

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ok so first of, this will take your bike to around 26-28 bhp at the rear wheel ! so if you've not road anything bigger than a restricted 125, take it easy... its not uber fast but its fast enough to catch you out..

ok so firstly, you have 2 options , you can either :

A: Have your original exhaust de-restricted (they usually have a cone in the downpipe, this has to be cut out, and then welded over)

or (my preffered option, and for best results)

B: Buy a race exhaust, ie jolly moto, jim lomas etc, this is a good choice http://www.125ccsportsbikes.com/forums//in...showtopic=20174
as these dont have any restriction in them....

ok, your about half way there, DONT take your bike out just yet, a couple more things you have to do for best results, firstly, you want a derestricted airbox lid and some appropriate jets, try craig for these, failing that try rob at mito mondo. As a general rule, your looking at around 10% bigger jets, older and newer mitos have different carbs so best to check with craig/mito mondo on which jets to go for.. you want to start a little big, and work your way down the jets... till you find the right one


How do i know if its jetted right you ask ?

for checking the MAIN jet is correct, you can either do it yourself ;

you need about a mile, where you can ride the bike flat out for a full mile, then you will need to pull in, hit the kill switch, dont let the bike rev down... or down through the gears just kill switch, then clutch in and stop....

now check your spark plug, black = jet too big, tanned brown = jet perfect, grey = jet too small (BAD) alter the jetting accordingly, and you good to go


you could get this done on a dyno, if your a little unsure yourself, for more info on jetting yourself, see http://www.amiles.com.au/rmr/SparkPlugReading.htm or http://www.bcchapel.org/pages/0003/pg11.htm

HTH
Kev
HI Kev Ive just bought a new Mito evo and i want to derestrict it Im putting in a 120 main jet do you think I should up the Low speed jet from 55 to 65 at the same time?

mike the bike
 

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Does not know Everything !
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For jets buy a derestriction kit from Rob at Mito Mondo, it has all you will need.

As has been said above, do all of the steps at the same time or ELSE will happen.

If you have specific questions ask them in the Mito forum as Gezzer stated above.
 

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my 2000 reg mito has been de-restricted and has had a v-force 3 reed block fitted, but wont do the ton, what could be the cause of this? could it be the front sprocket being a tooth too small? of the carb set up dodgy (when i blip the throttle is bogs down) or has the exhaust been done wierdly ?

any help will be muchly apretiated. Brad...
 

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Ok, straight to the point, No BS! Thanks.
Why is Mitaka sh*t? Do they have a history of failing? Or do they just not perform as well?
Can anyone shed some light as to whether Flat top pistons perform better than Domed?

Anything constructive, that will increase my current 31 Hp would be appreciated
You could get a 154cc kit, port and polish, get a 39mm carb, fit a +5hp nitrous bottle, even fit a small go kart turbo unit, speed is a question of money.... how fast can you go?
 

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no way are they geting 50bhp form anywhere. mitaka a sh*t, use all cagiva parts.
I'm guessing this is the project he was on about... http://www.racingsm.org/mito125ev.php

Bearing in mind LuFo's 2T-tuning reputation, I'd be inclined to believe the almost-50bhp-at-the-crank figure... but I doubt anyone in this country could achieve it...

I've read on a Portuguese website that they're getting 50ish Hp from their bike. They've got a 41mm PWK carb, and a Gianelli pipe, but apart from that, it would be hard to guess what else they've done, Porting, running Methanol, etc. I'm also unsure of whether that 50HP is at the crank or back wheel. If it's at the wheel, I'm all ears!!
Read the link above - it's all down to who does the tuning and how, and twas a handmade pipe, handmade CDI, hand-ported polini cylinder... none of this "buy a bit from a shop and bolt it on" mallarky I'm afraid... if you want that much power, it's gotta be done by someone with the know-how. Twas around 44-47bhp at the wheel.
 

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As far as i have found out the 125cc mito squish volume should be 8.8 cubic centimetres, for a 162cc it should be 14.4 cubic centimetres.

Thats for those who are upgrading or rebuilding and want to measure the squish properly using a syringe and oil.

Make sure you remove the exhaust pipe before measuring the head volume with oil as it will run straight down into the exhaust and get stuck in the expansion chamber if you dont.
 

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you know you could just buy a racing air filter like a K and N filter cheap and adds power! also, to an earlier question, have a look at dome topped wiseco pistons they are forged and so more revs are achieveable which means more horses! l8rs.
 

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Hi Everyone,

Why is derestricting so bl**dy confusing?
I got myself a full Arrows system and have been dying to fit it but have been scared off by all the talk of running lean and killing my Mito.
I've been reading the info on here, but still not sure how to do this properly.
There's a guy selling bike parts on flea bay who said "re-jetting is the worst possible thing you could do to a Mito and it will never run properly again", and yet you lot say re-jetting HAS to be done.
I'm sat here with a full exhaust system, Boyesen Reeds and an induction air filter - all still in their packaging.
I've tried the famous Rob at Mito Mondo but we seem to keep missing each other or picking bad times to call.
I got absolutely wasted by a shell-suited chav riding a spanking new RS125 with squeaky clean L-Plates on it the other day, so something has to be done - rapid.
I don't want to fit a bigger carb or anything else too complicated - just to be able to fit my new bits without blowing the bike to bits 500 yards down the road!
While I'm trying to catch up with Rob, does anyone else know the proper tried and tested full de-restriction process and roughly how much it's going to hurt my wallet?
I ride a yellow 2004 Mito which I've owned from new and any help would be much appreciated.
I'm new on here so don't hurt me if I'm going over old ground!!!

Thanks guys
 

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125cc Sportsbikes Supporter
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right you need a airbox lid the same as the one in my post above don't use anything else it WILL kill your mito not sure on what jets u'll need maybe someone will be kind enough to imform you failing that if u cant get rob via telephone send him an email goodluck
 
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