Originally Posted by Pattojnr (Post 5546842)

i just got a std version, i opened it up and was quite amazed at the crank and the liner. it is quite different to the Novas i have been running. i actually thaught about the design of this hole on the crank pin. to be honest i like the idea. its not really backwards, if one was to elongate the internal hole in the crank body, that would effectively double the surface area to channel the fuel to the rod. just my thaught, and with this to run a rod with the hole inthe rod also, this would double the amount of lubrication yeah ? the amount of metal around that crank pin, im sure it really hasnt weakened it too much ? there are so many factors why the pin might have broken on some engines, like hitting things on full throttle, screws coming loose, and jamming up drivetrain, etc, ill try it stock, see how it performs, but i will be making the internal crank hole a little bit bigger where there is alot of metal.

Originally Posted by bigredspeed (Post 5550510)

Sounds cool about making the hole bigger, which im really curious to see how long it will last you. Could be possible about the reason that you have listed that could cause the Crank pin to break, but why does it also break when the engine is brand new from the box and running on the first tank on the track with rich settings after coming of the bench after 3 Tanks of idle? i would rethink about drilling that hole bigger. But good luck anyway and keep us posted, like i said im intrested and i hope it works. Just might be another improvement that could done.
Cheers

Originally Posted by Pattojnr (Post 5552618)

well i do have a few opinions about this engine already. and maybe it was read wrong about the hole. im talking abobut the inner part of the crank, elongate the hole in the direction the fuel is coming in from. so this would effectively double the area to catch the fuel on the way through, but in no means to drill the hole bigger, that will weaken the pin.
this is by far the tightest engine i have ever run in. normally preheating and engine to 70-80 c works a treat. im having to get 100 + to prevent the piston from getting stuck on tdc. that is a huge stress on the rod and the pin. all care taken runnign in the engine, and keeping heat into it while it runs , all helps on the rod and pin issue. but i guess ill be seeing the results in a few weeks. adding the extra shim while running in will also help, and running it in with a higher oil content and 16% fuel will also help. i wouldnt be hitting the track with it in the first 2 tanks, its too tight, i have 4 tanks through it now , just my opinions thats all.

Originally Posted by vadn1 (Post 5553014)

I have the VZ-R engine modified by Uriah M, and he has elongated the rear portion of the crank just like you are saying. The Next time I have the engine apart I will take a picture of it and show you. I wraped a towel around the cooling head to keep the engine temp up, but yes it is still very tight with the added shim and approx 1/2 gallon of fuel through it. I use a heat gun to warm up the engine everytime and to reduce stress on the Rod.

Originally Posted by Pattojnr (Post 5552618)

well i do have a few opinions about this engine already. and maybe it was read wrong about the hole. im talking about the inner part of the crank, elongate the hole in the direction the fuel is coming in from. so this would effectively double the area to catch the fuel on the way through, but in no means to drill the hole bigger, that will weaken the pin.
this is by far the tightest engine i have ever run in. normally preheating and engine to 70-80 c works a treat. im having to get 100 + to prevent the piston from getting stuck on tdc. that is a huge stress on the rod and the pin. all care taken runnign in the engine, and keeping heat into it while it runs , all helps on the rod and pin issue. but i guess ill be seeing the results in a few weeks. adding the extra shim while running in will also help, and running it in with a higher oil content and 16% fuel will also help. i wouldnt be hitting the track with it in the first 2 tanks, its too tight, i have 4 tanks through it now , just my opinions thats all.

Originally Posted by bigredspeed (Post 5553118)

Im with you now, sounds like a good a idea, and yes Patto, OS motors are very tight and you do have to get alot of heat onto the crank and head to get it to idle on the bench without locking up,which is why i like to use Foil to wrap around the head while idling and keeping it nice and warm from the first tank.im Glad you mention the part about the Rod and Pin going under alot of stress from the first start up and everytime it locks,that cause heavy stress to a rod. But some ppl just dont want to believe you.would love to see it run after any modds you do to it. maybe you could YouTube it?:nod:
Good Luck with it
Cheers

Originally Posted by Pattojnr (Post 5582412)

i ran the motor yesterday and i can say it has a broad power band. smooth from low to high. was running rich still, but easily beat my fastest lap time while running rich. i am impressed, it is stock as a rock, and i feel there isnt much need to mod it much at all. the only thing maybe is for the factory to look at how tight the damn thing is, i mean does it really need to be so damn tight ? anyway, it ran flawless most of the day, well till i broke me car :lol:
i will look at getting another one soon as a back up for the states.

Originally Posted by Sp Racer (Post 5380169)

I used a standard, out of the box .21 VZR at the recent Vic. state titles , the best lap I did in the semi final was only .3 slower than the winner of the A main.

Every heat the engine just got faster and faster, 5 minutes was easy ( I used a Novarossi 2015 pipe ) - added 0.1mm head shim and used a P7 plug.

I loved the linear power band , and to be honest, I didn't feel as though I was lacking power anywhere against all the more fancied names (GRP, RB, Novarossi)

I reckon stick a ceramic rear bearing in one of these, a little tickle with the dremel and in my opinion you'll be rapt ! ( have not done this yet ););)

These engines would have to be the best bang for the $ out there