RE: The O.S. v-spec problem
 

a small shim here might be worth a try, have you any idea what you will use as a shim? because like mentioned earlier adding weight to that part of any engine increases the reciprocating mass & thats never a good thing, especially an engine that revs as high as a decent race .21!

RE: The O.S. v-spec problem
 

Aluminum is the preference and once that mod has been done it last's for gallons and gallons..
Proof are in results...[:'(]
Here are TWO OS TZ's with that spacer in them. They finished 1st and 2nd at the Pro sereies race. FYI: the gy in 3rd is Ross Deny whom I race with at my local tracks.
http://rdracingproducts.com/rpics/RCPro4podium1.jpg


Go here to debate it....[link=http://www.rdracingproducts.com/store/product_info.php?cPath=57&products_id=94]http://www.rdracingproducts.com/store/product_info.php?cPath=57&products_id=94[/link]

RE: The O.S. v-spec problem
 

The guy from the O.S. support forum say's the flywheel is not tight. He also said that some rubbing is expected. The rubbing should be light. I measured my used rod's against the new one's I got today, and the used ones measure .193" thick. The new rod's measure .198". So after they run awhile the get shaved down by .005".

RE: The O.S. v-spec problem
 

Hey Guys....

In regards to the VZB problem, I talked to a friend of mine the other day regarding the OS V spec engine VS a NovaRossi P5X or 421... Alan told me to go with the Nova because of the factory support of OS. He had to send his V-spec in for warranty repairs twice during the race season of 2005. Both were from major bearing failures. He told me that OS was not very interested in helping them out with the repairs. And on top of that it took several weeks to get their engine back. Not something you want during the race season! Alan is a very skilled professional Mugen sponsored driver that knows what he is talking about. I'm going with Novarossi when my CMB takes a dirt nap....

RE: The O.S. v-spec problem
 

0.005" wear is a lot (127 µm or 0.127 mm for metric guys) and the crank should be changed. If the crank pin is more than 0.002" out of round I replace it.

RE: The O.S. v-spec problem
 

mbxed-
Did he tell you that "your" flywheel was not tight?---Because mine was tight!!!----As for him telling you the rubbing was normal:) The next thing he'' ll tell you is to run the motor without a airfilter because that is "normal". Like I said befor OS knows they have Two major defects with the v-spec---------We just all hope they do what's right and fix it!!!

Update: The RB C5BB that i replaced the v-spec with runs like a champ------last week TQ'd with it----great motor----easy to tune-------Runs great!!!

RE: The O.S. v-spec problem
 

and does this sound like a good thing to anyone?

RE: The O.S. v-spec problem
 

RE: The O.S. v-spec problem
 

First let me say that I`m not trying to start any thing here. It plainly states in the manuel that there is NO warranty on the V spec due to the fact that it is a racing engine, that may explain the lack of intrest from O.S. to help out.

Are people running the VZR (on road) haveing similar problems? The VZR and V spec share the same block, backplate, rod, and bearings ,the crank is a different part # though. This may be reaching a bit, but has anyone haveing problems compared serial # to determin if there were mabye one or two production runs that have a problem ? I bring this up because there seems to be as many people without issues as there are with issues. Just a thought, now flame away.

RE: The O.S. v-spec problem
 

You are going to be VERY VERY happy with that C5BB.... After you get about a gallon through that engine your temps are gona drop 10-15 degrees and it will really wake up!! I have two of them and a WS7II and they are amazing engines. Also for anotr coice in pipes you should give the 2006 pipe a try, it will give you some amazing top end. I am not the best driver in 1/8th scale as I just started racing 1/8th scale at the end of last season but thanks to the C5BB I have no problem at all keeping up with the fast guys at the track. When I can keep it on all 4's I walk away from everyone but the two other guys running the C5. As for that OS issue I have seen way to many people waste hard earned money on these engine to just have them eat themself in a matter of gallons. I have seen it happen on TM's TZ's and V-Specs. Man the owner of my LHS is an OS guy all the way and nearly had me talked into a TZ for my Revo and a V-Spec for my 1/8th scale. We now have three guys at the track racing RB's and guess what... last I heard they were going to try stocking RB's.

RE: The O.S. v-spec problem
 

4xadict-

Manufacturing defect's are covered,and there's two of them:D

Rockymountain revo-

I love the C5BB, The pipe I have now is a 063---med torque----med power-----gas gusler[:o]. I'm going to switch to the 2020 or run a JP-2. I just ordered a RB TM928 for my CRT. The motor is running slightly richand the temps are very stable at 238. I have 1/2 gallon on it----I'm going to race tune it soon.

RE: The O.S. v-spec problem
 

The JP2 works great on the engine... Last time I raced I ran my JP2 because there are a lot of hacks and I didn't wana ruin my 2006 pipe on a meaningless race. It's kind of funny out here because nobody has really even heard of RB and even after seeing me and my buddies RB's run people still say the are just too expensive and then spend 300 on a V-Spec. Let me know how that 928 runs I have been considering getting into the UMT class so I can race in 3 classes this year, and if I do I was leaning toward the 928.

RE: The O.S. v-spec problem
 

No problem-

I was also told that once broke-in and race tuned(over 1 gallon) that a hotset-up was to run the RB 2020 pipe with a 6mm or 7mm carb insert----plenty of low to mid power with no loss at the top and you can get 9 1/2 min-10min run time with the 6mm.:D.

RE: The O.S. v-spec problem
 

I fail to see how a 6mm restrictor will give the same as 8.5 or 9mm. Simply not true.

RE: The O.S. v-spec problem
 

The engine may not have the all around power to get you to top speed as fast, but what he is stating is that there is no loss in top speed, the restrictor does not restrict RPM's. I run both my WS7II and my C5 with the 8mm restrictor and I can honestly say that on the C5BB going to a smaller restrictor will probably improve lap times because there is soo much power it's tough putting it all to the ground.

RE: The O.S. v-spec problem
 

Just thinking about physics here.... Restrictor plates in NASCAR for example = reduced power.
Not arguing about reduced lap times, that very well might be the case. ;)

RE: The O.S. v-spec problem
 

sman-
No offense to your knowledge of nitro engines but as I described in the post-You can use the RB c5bb with a RB2020 pipe and a 6mm insert to tune that motor to run strong at the low to mid power range without loss at top speed and be able to get 9 1/2 to 10 mins run time.---The c5bb generates more torque at the low to mid power range and the 2020 pipe is set to tune that motor for max torque and max high-end power- Thus by using the 6mm on that motor(c5bb) you can get better fuel consumption(less pit stops) and the low-mid power is more controlable(wheel spin=slower lap times)but still strong.

Hope this helps

RE: The O.S. v-spec problem
 

i've problem tuning my vzb V-spec. At the end of the long straight, the engine rev will not down to an idle, just after a few second it will. I know some people saying that is overheating and to open the HSN a bit. But if i richen the HSN needle i couldnot get the performance i like from my engine, so maybe you people can help me. Is the LSN and Mid needle have anything to do with this? Btw the engine temp. is 120C

RE: The O.S. v-spec problem
 

When you run the car hard around the track and bring it in it should idle high for a second and drop to a nice idle..... If it idles high longer than that you should lean the LSN some.... this will require you to lwer the idle now as well and you may need to richen up the HSn slightly as well.

RE: The O.S. v-spec problem
 

thanks for the help. i'd try your suggestion, i adjust the idle screw very low just untill the the engine not stall, it help on the idle-high problem a bit, but now if i backup the thortle sometime the engine will stall and would'nt idle nicely. so what is the problem? is the engine worn coz i notice some play on the conrod and crankpin

RE: The O.S. v-spec problem
 

[/quote]Aluminum or copper would work. Aluminum would be best.
[/quote]

how thick/width is the spacer? any picture

RE: The O.S. v-spec problem
 

hi all

being a new member in the forum, i've lot to learn frm y'all. was browsing the net in my relentless pursuit for finding the cure to my "aching" v-spec. was shocked to see that there are peeps out there who had went thru hell lotsa things in making their v-spec runs smooth again. well...guezz i landed myself in the correct place. here i am...me, and my v-spec and the grinding of backplate issue problem....been 2 gallons on the engine so far. hole in my pocket as a result of the v-spec. advise needed....... gosh finally!!!!...rc-uni