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Discussion Starter #1
fast by ferracci airbox frame questions

i recently put the ferracci airbox frame in, i had an semi open hacked stock one before, and i noticed
the bike loses power/stumbles/runs rough at about 80mph, as fast as i decided to test at, about 75% of comfortable max. i was pulling about 5k rpm. i notice that at
lower speeds at the same rpm, it did not do this, and with the exception of high speeds, runs better.
now is this from running too lean or turbulance over
the filter from the high speed forward wind pulling air away from the filter or just from the very cold air and moisture (40°) or from the force of air blowing into the filter.
i am running the stock jets and was running a little rich prior.
according to Fast by ferraci i did not need to rejet for the frame.. just wondering. .. is this why the DP performance
kit has the raised edges.. .. the fast by ferracci airbox frame is at filter height offering no air block.

anyone come up with this, or have 2 cents worth.. ..

i also notice it made the bike run hotter, so i assume it is running too lean.
i drove only 7 miles (10 minutes) in 40°F at 30 - 70 and it felt like the bike was running much too hot, i would say by touch at various places, fins, crankcase, heads... about 140 - 180°.. hot to touch, but not too hot to hold your hand on for a duration, hot for winter in sf, near overheating, i am guess-timating the temp, but that seems about right. so i guess i am
taking the thing off 'til i sort it out, the bike feels much hotter than usual for the riding duration and outside temperature.. glad i picked a cold night to freeway test it on. kind of gets me, i asked ferracci if there was anything i needed to do, like jets or mixture and they said "no", given a hot day and a long ride, i could have fried the engine, in particular, the pistons.

anyone know of a good place to take it to get it tuned in SF, CA.
 

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It probably is running a bit leaner, I wouldn't think that it's running lean enough to do damage, but that probably is the increase in temperature you're feeling.

However, the stumbling at high speed wouldn't be caused by the motor running lean, and probably is cause by turbulance of some kind. did you accidentally disconnect the air density hoses or move them out of still air? it would be really easy to do when playing with the airbox. If a vaccum was put on those hoses by airspeed over their openings you would have a lot of the same symptoms you have.

Check it out.

Justin
 

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Discussion Starter #3
it actually felt like the bike did not want to go faster and i did not want to push it when i noticed the performance decrease and ended the test and checked the engine temp. basicly i drove to one location with the hacked stock one in and i then drove back the same route with the new completely open frame and compared the two. at the mid point i check the temp by hand feel and let it sit about 10 minutes. on the reverse route, the engine was significantly hotter.

i checked the vacuum tubes, the 3 that go into the grey plastic things, they were fine.

i figure if it was running lean enough to damage the engine, i would have starting problems and i would have noticed it at lower speeds as well i did not let it get to the overheat point, but one can damage the pistons if it does overheat and it is running lean, something to keep in mind that it is worth having a pro tune it up for the summer.
 

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Why don't people fill in the "Bike Info" before asking questions like this??? ::)
Same for location, but you at least gave us a hint on that one.


You didn't bother to tell us what sort of bike it is. From your description, it sounds like you've gone from a stock airbox to an open airbox, which will make the bike run much leaner. If it's carbureted, you'll have to rejet (see the Carb Jetting FAQ for details). If it's fuel injected, you'll have to get it remapped.

What you're experiencing sounds like standard lean condition. If it's 40 degrees outside, I would doubt that the engine is running too hot regardless of how lean it is. Normally it's difficult to keep the engine warm enough when you ride at such temperatures. You'll have to spend long periods at full throttle to damage your engine from being too lean.

The best place to take any Ducati in the San Francisco Bay Area is Nichols Mfg in Milpitas.
 

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Discussion Starter #5
sorry, i am a sort of noob, well i had an id and bike info a long while back but forgot the id name so i just did a new account, i moved overseas and then moved back.

the bike is a '99 M900S. it has low mount staintunes with the baffles removed. the only other mod affecting intake is the canister removal.

i had a hacked stock airbox, basicly just took the rubber vents out and made the holes bigger, doubling the intake potential. it was running rich prior to doing this and after opening up the box a little, i noticed a great performance increase.

i did not check the plugs, the temp guaging is just a crude test to indicate a potential condition.. fast by ferracci told me i did not need to do anything, it was good to go out of the box.. i was skeptical and decided to do the crude test... as i have read the carb jetting faqs and did a topic search on the frame before asking. i expected it to run lean, i wanted to see if it was lean enough to be an issue before i take it to have it tuned. anyway, the test was good, it told me i need to do more to it if i want to run a box like this.

yest it was painful to take the frame out and put the plastic box back in my precious, the frame looks really nice in it... i was
actually going to put the hacked stock box back in during the rainy season that is about to begin, and put the frame back in for summer..just wanted to see what i needed to do.

i take it i am going to have to put a stage 3 rejet kit in, so i might as well go for it and put pods in and make a small air dam to reduce turbulance. ferracci may not have considered adjusting the mixture as really doing anything and i could just do that to correct the overall lean, but still have dips in performance,.. and they did not know my setup... i have opened up aftermarket pipes... i take it since i had a major dip in performance at higher speeds, i would definately have to go with a jet kit if i wanted good allaround performance... the frame uncorrected give great city low speed performance.

i think the condition i experienced was a combination of the cold moist air rushing in forcefully into the filter and an already lean condition from the frame... i asked the question as i was wondering if i just need to correct the lean and jetting or if turbulance was an issue.

i know i am just being overconcerned about my precious, ... i know... the engine it pretty tough.. it has to be to be aircooled... so tough they did not even feel the need to put a tach or temp guage stock on it.......... i did not need a tach until i changed the gearing and would not really need the temp guage unless i change the intake or other factors...
 

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I wouldn't be concerned about turbulence near the air filter. I've never heard of anyone identifying turbulence as the main cause of an incorrectly running Monster engine.

However, opening up the airbox has been proven to make the bike run more lean, and you only notice it at higher engine speeds and at more than half throttle.

Rather than go with a Stage 3 jet kit, which implies Dynojet, I would suggest that you get a Factory Pro jet kit and go with the largest of the three main jets. The Factory Pro jet kit is just a bit easier to deal with.

Do you feel like you could handle installing a jet kit yourself?
 

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Discussion Starter #7
i have rejetted before, i did a few kawi's and ran pods.. but the pods were located behind the engine. i did not even use a kit, i did it using different jet sizes until i got the best overall performance... took up to 3 months to get it perfect.

on the monster, well i am a little insecure about doing it. i know i could and how to. i feel that sometimes for the peace of mind and
getting it done right the first time, it is worth having the pro do it, hopefully i can get someone who will let me watch or assist and learn from it.

i was acutally hoping the frame would run well enough with just a slight performance dips, did not expect a major one and the
increase in temp, so i could run it until i took it somewhere to have it tuned...

i do not have a garage as well now.. so i am not sure i want to do that on my sidewalk even with being able to bring the carbs inside.

so the factory pro kit you do not have to change the needles.. i was thinking about going with the pods and was warned against it because of the location and it being a twin...
 

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ntula said:
so the factory pro kit you do not have to change the needles.. i was thinking about going with the pods and was warned against it because of the location and it being a twin...
One of the most important things in the Factory Pro jet kit is the new needles. The stock needles have almost no taper, so you can't do much to tune the midrange. The Factory Pro needles have quite a bit of taper and you can easily tell the difference when you move them up or down a notch. The kit also comes with new springs for the slides. I don't know how much difference the springs make, but I used them just to be sure.

It's probably time to start calling dealers and bike shops to find how how much they charge to rejet. You might as well call Factory Pro in San Rafael too. That might be the best place of all to have the work done.
 

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Discussion Starter #9
i will try that and call factory pro to do it all.

i can't imagine a rejet being more than 2 - 3 hours labour.. i mean, me the novice mech can remove, tear apart, clean, rejet, rebuild, and install a set of 4 carbs in 2 hours... the duc does have a lot of hoses going into the carbs... that is one thing i notice...

i will give them a call, as well and ask them about the pods... i would rather run the pods.

thank you for the info and advice.
 

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Another good place to take it is Desmoto Sport in SF. [thumbsup]The service there is very good, and if you live in or near SF, it is more convenient than going to Nichols.
 

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Discussion Starter #11
it is easy to forget desmoto has that back area where you can sit down and discuss exactly how you want your bike set up.

'spose i should keep it local and give them the first shot at it.
 
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