03 f12 malaguti phantom wont go over 40 mph

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schenk410
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03 f12 malaguti phantom wont go over 40 mph

Postby schenk410 » Mon Apr 12, 2010 5:38 pm

my f12 phantom lc will not go over 40 it accelerates fast as hell but when im accelerating it gets up around 40 and its trying to over rev which is like 11000rpm i put marks on the variator and rear drive plates to see if the belt was being fully used and all my marks were rubbed off the belt thats on it is a polini 248.040.1 brand new only 150 miles on it everybody says with the 70cc airsal kit the arreche 19mm carb with high flow polini air filter 85 main jet and turbo kit dual pipe exhaust it should do 60 mph i have a stock variator with 4 gm dr sliders and stock clutch and drum i beleive but it has a yellow torque spring and red clutch springs... any help would be very appreciated thanks

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F10Pilot
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Postby F10Pilot » Mon Apr 12, 2010 6:54 pm

I'd say either the clutch is slipping or maybe contra spring is sacked and belt is slipping. Are the clutch and contra springs new?

Are you sure you're using the correct length and width belt? Your friends are correct, you should be seeing much higher top speed. The belt listed for your bike is 248.040 I'm not sure if the .1 is the same or maybe it's the EVO belt or what.

Where are you from? Great to see more Malaguti owners in this forum.
Malaguti F10 - Flies like a butterfly - Sounds like a bee.

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schenk410
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Postby schenk410 » Mon Apr 12, 2010 7:02 pm

Well the yellow contra spring was already on when I got it so was the red clutch springs if the yellow spring was bad would the belt still fully travel on the variator and rear pulley ? I'm in harford county md I'm thinking it's a clutch slipping it's a stock clutch and drum also I took the cover off while it was running and the belt was slapping up and down in the trans does that mean to long or stretched thanks

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F10Pilot
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Postby F10Pilot » Mon Apr 12, 2010 7:14 pm

I only thought slip because the marks on the drive faces were worn off. So you would think the belt is using full travel - which I don't think it would go all the way down in the back if it was that much too long.

Yes with the contra worn out the belt would fully travel, but if it was slipping you'd think it would slip mega on acceleration also. So probs not that.

Did it work fine before? What did you change prior to the problem? Belt and Rollers or the whole build is new?

How does the new belt compare to the old belt? Shorter longer narrower?

I'm going with wrong belt but I'm generally wrong 2-4 times before I hit these things.
Malaguti F10 - Flies like a butterfly - Sounds like a bee.

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schenk410
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Postby schenk410 » Mon Apr 12, 2010 7:20 pm

i bought it off a guy it had no belt on it but it did run it had dr pulley sliders 4gm and a turbo kit dual pipe exhaust and the red springs and the yellow spring he told me it did 65 ?..... i put a new belt on it and it would do almost 40 then i did the 70cc airsal t6 and the 19mm arecche and bigger reed cage and bigger intake manifold with the 85 jet accelerates faster but still only does bout 40 max then its overeving. i only paid 150 for it which was good price for an f12 phantom lc but u dont think its a clutch? bottom line should the belt be slapping around ad idle and b making a noise?
Last edited by schenk410 on Mon Apr 12, 2010 7:52 pm, edited 1 time in total.

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F10Pilot
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Postby F10Pilot » Mon Apr 12, 2010 7:51 pm

If the clutch was not locking up it seems like it would slip on acceleration also.

Assume you tried heavier rollers?
Malaguti F10 - Flies like a butterfly - Sounds like a bee.

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schenk410
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Postby schenk410 » Mon Apr 12, 2010 7:54 pm

no i didnt try heavier rollers? would that make it go faster and rev lower? i have 4grams what weight do you have and would changing the variator do anything if i got a overange were the weights go farther out instead of stopping im getting lost with this? :? well the clutch drum does have a blue spot about 3 inches long on it

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F10Pilot
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Postby F10Pilot » Mon Apr 12, 2010 9:00 pm

Yes I think the most obv. problem would be rollers too light so not shifting down but the blue spot would indicate clutch slip.

I'd try some 5-6 gm rollers first though.
Malaguti F10 - Flies like a butterfly - Sounds like a bee.

kwaad2
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Re: 03 f12 malaguti phantom wont go over 40 mph

Postby kwaad2 » Wed Apr 14, 2010 5:31 pm

schenk410 wrote:my f12 phantom lc will not go over 40 it accelerates fast as hell but when im accelerating it gets up around 40 and its trying to over rev which is like 11000rpm i put marks on the variator and rear drive plates to see if the belt was being fully used and all my marks were rubbed off the belt thats on it is a polini 248.040.1 brand new only 150 miles on it everybody says with the 70cc airsal kit the arreche 19mm carb with high flow polini air filter 85 main jet and turbo kit dual pipe exhaust it should do 60 mph i have a stock variator with 4 gm dr sliders and stock clutch and drum i beleive but it has a yellow torque spring and red clutch springs... any help would be very appreciated thanks


I've got a 2002 F12LC Mine is 100% stock, minus a exhaust modification. (I sear, I got the pictures taken, I just need to upload them now!)

At 10,000RPMs I'm pushing 50mph. (so says the wish-meter, I'm getting 43 on the GPS)

And I'll just say this, which makes me think we BOTH need new gears. I have a TON of power, up until 9000 RPMs, which, funny that, is about 43mph(says the dash). I have my carb tuned in, where I'm getting my best power at 8250-9000rpms. A few things I would like to point out...
1. 11,000 Overrev, is for stock engine, you are NOT over-revving the new cylinder... unless you didnt change your crank... which I would do... before riding it. :)
2. Does the engine RPMs go up, after the thing shows 11,000 RPMs... I'm not 100% positive if our tach will show higher numbers? (my record on stock engine down-hill was 10,500, and it sounded like it was gonna blow up)

I'm guessing you (and I) need a new gearbox, however I'm going to wait on that until I get a new cylinder kit for it, because I want a specific top speed, and I need to find where the engine(I dont have yet) revs to before I can find that. :)

HOWEVER it dont make much sense, your revving at 11,000 and only getting 40max. I can get 46 out of my 99.9% stock 2002 F12LC... you should easily hit 50!
Check to make sure the belt is going ALL the way to the inside of the clutch pully. I have a funny feeling the belt is to large, and it IS traveling all the way to the outside of the variator, however is it going all the way in, on the clutch? As that would explain a 10-20% speed loss?

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F10Pilot
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Postby F10Pilot » Wed Apr 14, 2010 5:38 pm

It could be that the U.S. market F12 has ridiculous high final drive gearing but sounds more like something is wrong. I would think the F12 would have had the same or lower gearing than a Zuma (same block but onroad use) from the factory.

Changing the final drive gears may may your speed higher without actually solving the problem of something slipping or not being fitted correctly which is not good.

Kwaad - I'm dying to see this exhaust mod. If you've got a briggs&stratton lawnmower can welded to your stock headpipe you're officially my new scooter hero.
Malaguti F10 - Flies like a butterfly - Sounds like a bee.

kwaad2
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Postby kwaad2 » Wed Apr 14, 2010 5:45 pm

F10Pilot wrote:It could be that the U.S. market F12 has ridiculous high final drive gearing but sounds more like something is wrong. I would think the F12 would have had the same or lower gearing than a Zuma (same block but onroad use) from the factory.

Changing the final drive gears may may your speed higher without actually solving the problem of something slipping or not being fitted correctly which is not good.

Kwaad - I'm dying to see this exhaust mod. If you've got a briggs&stratton lawnmower can welded to your stock headpipe you're officially my new scooter hero.


Pfft, I'll upload it now... gotta figger out how to get it off my phone... haha

But yeah, I *KNOW* I'm not getting slippage. I can tell when my engine hits the end of the vario... and it's at about 42mph... from there, the RPMs climb to 9500/10000 and speed is at around 46... He has another problem, why he cant hit 40+... but... it's not gonna do over 55 I dont think... But I'm thinking the belt is to lose... HOWEVER... It's not slipping.

Let me try to explain.
At an idle, the belt IS slipping. Once the weights start to close the vario pully, it will then build tension... However at a lower ratio, than it should be at. As once the tension is there, there will be no slip, as his belt, at high RPM, will be as tight as ours... however the clutch pulley, will wont be all the way open.

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F10Pilot
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Postby F10Pilot » Wed Apr 14, 2010 5:57 pm

Any Polini experts around that know if the 248.040.1 belt is longer than the 248.040?
Malaguti F10 - Flies like a butterfly - Sounds like a bee.

kwaad2
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Postby kwaad2 » Wed Apr 14, 2010 6:14 pm

F10Pilot wrote:Any Polini experts around that know if the 248.040.1 belt is longer than the 248.040?


As seen in this document...
http://www.polini.com/dep/CG_04.pdf
248.040.1 is the CORRECT belt... So my idea on wrong size belt seems to be wrong... so...

Clutch Slippage, Belt slippage, something... no good ideas from me about that tho. :(

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schenk410
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Postby schenk410 » Wed Apr 14, 2010 10:35 pm

Does anybody think maybe my top speed problems will b my stock variator with 4 gm dr pulley sliders

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StepVino
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Postby StepVino » Wed Apr 14, 2010 11:00 pm

The only idea that fits is a slipping clutch or belt, otherwise
something in your original checks is incorrect. I mean you
shouldn't be able to have the lines rubbed off on both pulleys,
11k rpm, and be doing only 40mph. It just doesn't compute :).

Do you still have your old belt to try?
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