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Old 10-02-2007, 02:59 PM   #16
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I have never owned a V-spec but have torn down and pinched a couple for people. Biggest complaint I've heard is the crank pin wears fairly quickly as compared to some Italian motors. Last time I had one apart I checked hardness of the cranks. The v-spec was 40 rockwell, the Novarossi I checked was 54 rockwell. That is a pretty big difference, 40 is not really that hard and explains why they wear a little sooner.
When you tear them down use a mic and check the crank pin and turn and recheck all the way around. All cranks will only wear on one side, as the piston pushes down.

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Old 10-02-2007, 03:36 PM   #17
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JP Mods V-Specs have a custom crank ,not even close to the regular V-Spec ,I beleive it is actually a NovaRossi crank, only thing I noticed that was different from a standard Nova crank was the crossdrilled hole for lube into the crank pin journel. Like I said before, only issue I have seen ,and it was on every single one I took apart Except the JPMods , was the rear main bearing with gauled shavings under the bearing , and everyone was in the same place too! looking at the rear it would be at 10 o'clock.
If your not a motor guy DO NOT TAKE OUT THE BEARINGS !!! LEAVE IT TO SOMEONE THAT KNOWS !! These engines are costly and one little boo-boo can cost you an engine !
The V-Spec is going to be my engine of choise for next season , I am straying away from my love of the NovaRossi 367 is a bag of ()() !
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Old 10-23-2007, 02:42 PM   #18
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As for the ceramic bearings up front, if the tolorance on them is on the loose side (which they are if it is for a high heat app.) the crank moves around in the front too much causing the crank to actually rub the case , this robs power and makes things run hotter than normal . Not saying all are like this ,but you need to watch out for this. Pay close attention to the case and crank just behind the front bearing!
I was of the impression that ceramic is used because it does not expand as much due to temperature therefore they can make the bearing tolerances smaller not larger as you suggest. There would be more slop in a standard bearing due to the clearances required to allow the steel balls room to expand. You just need to make sure you buy quality ceramic bearings like TKO etc as if you buy cheap 'anything' in this sport it costs you in the long run.
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Old 10-23-2007, 03:17 PM   #19
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Oh Yeah, IMO OS is the way to go, I have been running a V-Spec for almost a year now and up until last sunday it was running as strong as ever. Very easy to tune and holds its tune extremely well, excellent fuel economy and awesome power. I replaced both bearings to ceramic after about 5 litres (a must as the standard ones in the Blue head V-spec are its weak point).
Last sunday, 12 mins into the 20 min A main with a 3/4 of a lap lead my engine started to run lean under acceleration and flamed out, my pit man got it started and after a lap it flamed out again only to find that the Carb had fallen apart (see picture below)

Unfortunately this was not spotted straight away so while trying to start my car on the starter box it was sucking dirt straight into the engine through the side of the Carb.
I am now considering buying an OS Speed and will look at rebuilding this engine and keeping it as a backup.
Does anyone have any experiences with the Speed motors and can advise which is better, the Alloy head or the Magnesium head, please give reasons and not just vote for one or the other.
Cheers guys.........Dave
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Old 10-23-2007, 05:05 PM   #20
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Im not going to knock os engines, they make great power. I have a 07 vspec, and it basically has no pinch left after 2 gallons. Dont know why but I noticed it was starting to flame out after 5 minutes and took the engine out and the flywheel turns over easily by hand.
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Old 10-23-2007, 05:08 PM   #21
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Im not going to knock os engines, they make great power. I have a 07 vspec, and it basically has no pinch left after 2 gallons. Dont know why but I noticed it was starting to flame out after 5 minutes and took the engine out and the flywheel turns over easily by hand.
Hi Tony,
What method did you use to run it in?
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Old 10-23-2007, 05:12 PM   #22
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Quote:
Originally Posted by mremtr View Post
JP Mods V-Specs have a custom crank ,not even close to the regular V-Spec ,I beleive it is actually a NovaRossi crank, only thing I noticed that was different from a standard Nova crank was the crossdrilled hole for lube into the crank pin journel. Like I said before, only issue I have seen ,and it was on every single one I took apart Except the JPMods , was the rear main bearing with gauled shavings under the bearing , and everyone was in the same place too! looking at the rear it would be at 10 o'clock.
If your not a motor guy DO NOT TAKE OUT THE BEARINGS !!! LEAVE IT TO SOMEONE THAT KNOWS !! These engines are costly and one little boo-boo can cost you an engine !
The V-Spec is going to be my engine of choise for next season , I am straying away from my love of the NovaRossi 367 is a bag of ()() !
.......................

Last edited by Maximo; 01-08-2008 at 07:12 PM.
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Old 10-23-2007, 05:28 PM   #23
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I let it idle a tank or so, Then heay cycled it every few minutes, got it up to temp and shut it down. Let it cool and fired it backup. os wants the user to run a gallon of fuel for break in, thats crazy, I have seen guys skip break in on other engines and go right to race tune with good resukts
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Old 10-23-2007, 06:16 PM   #24
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Quote:
Originally Posted by tony montana View Post
I let it idle a tank or so, Then heay cycled it every few minutes, got it up to temp and shut it down. Let it cool and fired it backup. os wants the user to run a gallon of fuel for break in, thats crazy, I have seen guys skip break in on other engines and go right to race tune with good resukts
Risking the posibility of opening up a huge can of worms by suggesting one method of running in a motor is better than another I will just say that I also used the heat cycling method and the engine performed like a dream.
It seems the idling of a tank or so is no longer required, now even the OS manual doesn't even suggest idling a tank through.
I would suggest anyone about to run in a motor is to find out as much information they can and to go with the method that makes sense to them. I use the heat cycling method as described in this link if anyone is interested.
(http://www.johnnycoolguy.com/JCGR/ma..._break-in.html)

Something I think everyone agrees on is to never over-rev, over-load or over-heat the engine during the run in period.

Cheers.......Dave
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Old 10-23-2007, 08:30 PM   #25
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from what i recall OS has fixed the bearing issue , just got my V-spec and cant wait to have it run in ready for race.
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Old 10-23-2007, 08:39 PM   #26
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from what i recall OS has fixed the bearing issue , just got my V-spec and cant wait to have it run in ready for race.
I hope so as this was the only downer with the motor as you knew you have to strip it and replace the bearings soon after buying it which put a lot of racer off them.
It has definately been fixed on the O.S. Speed version of the V-Spec as they have replaced the main bearing with a Ceramic bearing.
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Old 10-24-2007, 04:46 AM   #27
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a JP Mods V-Spec has a coated crank nothing more, its not anything custom
Well I beg to differ, the cuts and overall shape of the crank in a JP Vspec ARE different from a stock V-Spec ,at least they are on the one I have ....
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Old 10-24-2007, 07:09 AM   #28
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Well I beg to differ, the cuts and overall shape of the crank in a JP Vspec ARE different from a stock V-Spec ,at least they are on the one I have ....
nope its just a modified + coated stock OS crank....... everyone loves to hype up these motors, but the truth is always much less glamorous then the hype.....
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Old 10-24-2007, 05:32 PM   #29
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Do you own both versions ?? IF so were they both new ? Well I have both and they are different! The sleeve is also different ,same port configeration but the JP has more cuts/ modified work done to it ! The JP gets lousy milage compaired to the stock version, but spools up WAY quicker
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Old 10-25-2007, 12:03 AM   #30
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what are the factory needle settings on the carb ? someone please help!
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