jeffreylin

Yeah, I am in NYC for a friend's wedding. I am bummed that I missed the race. How did you do?

Francis M.

iTrader: (2)

not good at all.

kewdawg

iTrader: (3)

Common knowledge to whom? You're telling me, that you think the crank issue is purely bad craftsmanship or poor quality? Is there a thread on r/c tech for this engine? How many people are saying this (other than those in your immediate, geographical area)? I've had my Sirio Evo 2 World's Edition for three months, ran a little over a gallon thru it and the engine runs insanely strong from start to finish. Feels like I got a damn HEMI in my nitro touring car!!!

centax error!

jeffreylin - are you talking about the caster clips? i'm talking about the small palstic that got 4 smalls holes that holds the hinge pin.

CE!

rcosmax

2 bits of news from me:

I finally got a day without rain to race my rrr with new 7075 chasis. (been trying for almost a month now ) I absolutely love it. The tracks I run at are smooth with decent traction and on sunday the car was dialed. the new chasis seems to take out the super aggressive dive/turn in that the rrr can have sometimes unpredictably. i also felt it could be more hooked up and run a bigger rear droop without feeling the danger of highsiding that alot of rear droop can sometimes give. this also made the inside tight and fast line seem more drivable. so with a few setting changes and a few practice laps i was really loving it. i finished third on the day behind a pro driver that showed up outta nowhere to clean up and the track's local fast guy that also drives at the pro/ semipro level here in japan. On top of this I was really happy with my driving. i touched two corner markers all day with only minor roll overs . part of this was because I was using my backup/backup OS.12 tr mod. It doesnt have near the rip of the other engines but it was faster and easier to handle on the tight and very long infield section at my track. so in all I have two big thimbs up for this new chasis....but make sure your bats are well charged because it is a job to change them out.

the second is a coment about the sirio evo 2 worlds. This motor is insanely fast! It really is a missile. At the three local tracks I drive at 4 of 12 sirios have had massive crankpin failure that totally grenaded the engine... part of it is because the engine revs to the moooooon and will rev till it explodes. If you dont tame the rpm with correct gearing it will grenade. i also feel that there is a bug that needs to be worked out with the crank.... maybe it is too hard or etc etc but to have a quater of these engines fail exactly the same makes me think something is up. All these drivers are experienced and have been racing for a very long time so it isnt bad tuning /abuse.

happy racing.

jeffreylin

That adjusts the roll center.

Kyle Hazell

iTrader: (17)

If you read around you will understand why its common knowledge. Im not telling you anything other than there is a problem with these engines and they detonate.. The reason for that, well i dont work for the manufacturer, nor claim to be an expert in crank design or the materials used/processes involved so i cant answer that.

Im glad your engine has not detonated, you have got good value for your money. The same can't be said for a lot of other people...

Regards

Kyle

jeffreylin

I think if you contact the dealer Sirio will replace the broken crank free of charge.

kewdawg

iTrader: (3)

This is why I said "user error" could be a possible culprit. Name any high performance engine that won't detonate, if, allowed to rev to the moon for any extended lengh of time? Improper gearing can overwork even the toughest sport engine... quick - and a high performance engine, made to perform at exacting tolerances, even quicker. We don't have to be "rocket scientists" to figure this out. Even well seasoned nitro racers / tuners mis-judge and / or make mistakes. I know plenty who still use the older methods, they've always used to break-in, tune and gear these new engines without consulting the instructions included in the box (How many of you, out there, actually read the directions for proper care?). I believe we're not factoring in, that, there are newer technologies and materials going into making these new powerplants. The processes for constructing these "missiles" with a heatsink head, are quite different from just three years ago. We all talk about how unbelieveably powerful and finicky these new powerplants have become, but we don't stop to question whether our previous methods to get them running at an optimum are still useable?

My 2 copper pieces.

rcosmax

I agree but these guys are not novices and the engines arent free reving, they let go on the straight stretch. Maybe only a single tooth difference change in gearing... but normally you get X amount of speed out onto the straight stretch but get a good exit speed and poof, the engine lets go. I have seen many blown engines but usually a crank pin letting go happens in an older engine or from a run away... free rev... or maybe a rod letting go and jamming. These sirios are detonating early in the engines life around 1.5 gallons of use and not even in a long main. It isnt tuning because they all were on the conservative safe side of max power. I am not critisizing or saying it is a bad engine(in fact I am amazed by it) I am just saying that maybe sirio will change materials and processes to stop this in the future. If it were user error then you would expect to see an equal amount of other engines failing the same under the same circumstances but they dont. So it would seem that something needs to be changed a little.

my 2 yen.

Racing4Evo

iTrader: (2)

When you guys say "detonating" are you reffering to engine failure or detonation associated with combustion? I have seen my friend's Collari show excessive wear on the crankpin but that was because it was undershimed. Perhaps the engines you've seen fail are undershimmed. An undershimmed motor will incur the most damage during break in.

Joehwee

iTrader: (3)

Sirio have been winninig most of the time in my country and so far I have not come across any problem other than some leaky carb from EVO 1. Even since the EVO2 was out, everything seem to be done right. Apparently some of the drivers have been running the EVO2 for the whole race seaon with the original conrod. The 2 top drivers from that team have been racing the M.Collari EVO2 for 7-8 races now and still going strong.

I dun really think the Sirio have problem, perhaps wrong gearings or fuel with too little oil could be the problem.

centax error!

Thanks and I understand that there is no way I can adjust front kick up and this tuning option is only common to EP cars,right?

jeffreylin

You cannot adjust front kickup on the RRR, but perhaps you can with another car.

rcosmax

sorry i shouldnt have used detonating.... i meant breaking of the wrist pin. I havent driven one, or messured the head clearance so this could be very possible. Maybe it is all driver error but I just wonder why other engines arent doing the same. anyway i think it is really fast... the fastest engine i have seen run and I dont even have a complaint i was only commenting that I have seen the new sirios blow up too.

anyway back to the rrr