Yasuni Blew the Corsa....What next?

K, so the Yasuni blew the Corsa cylinder easily. However, I'm not convinced it was an actual Corsa. The Corsa is supposed to have a cast iron head, mine was aluminum.

So my next question is, which cylinder should I get now. One that will be able to handle the Yasuni C16. One that will be able to hand a 5 mile work commute with a 1 mile uphill. I'm looking to buy immediately so any input would be greatly appreciated.

MHR Rep ? Where to Buy?
Polini EVO ? Where to Buy?

 

not sure on shipping costs to your part of the world, but most of us buy from the german sites

make sure you check availability 1st though, as long as the item is in stock,
delivery is usually pretty swift

heres 2 i use...

# www.scooter-attack.com
# www.scooter-center.com

 

So which cylinder would you recommend, the MHR Rep, Polini EVO, or Polini Corsa (a real one this time and not a Contesta).

I'm leaning more towards the MHR Rep. I have a full MHR transmission and I've been quite happy with the durability of their product. The MHR Rep should be able to handle the Yasuni C16 correct?

And I've ordered through SIP, are most of you guys pretty satisfied with them?

 

Polini Evo for raw powah ive heard. :msn1:

 

yeah iv seen sum evo 2's in actiona dn theyr sick , the revs those cylinders can reach are mental

 

an evo kit wont last 10 minutes on idle with stock crank.

the malossi mhr rep is the best choice in my opinion

powerfull but stil good for everyday use...

 

get a cast iron 70 kit as its more reliable better to be safe than sorry

 

MHR-rep will go nicely with your c16 pipe

and yeah s.i.p are pretty good as well

 

So what do you suppose caused this?

 

lack of airfilter :L

 

Lack of air filter? I've got a UNIfilter on it. Was it the Air/Fuel mixture screw? Running lean?

 

running overly rich + overheating

 

Overly rich? I thought that running too rich would be the safer way to go to prevent blowing the motor? Wouldn't running to lean cause overheating and blowing the motor?

Anyone else have input?

 

the plug is wrong.

wrong heat range or something as it has been doing away at the top of the piston.

 

Well it's an AC motor. I originally thought that this was a true CORSA motor because of the black cast iron cylinder. But the cylinder head is cast aluminum, which leads me to believe that is was a wimpy Contesta motor instead of a Corsa. I was running the BR8EIX plug, which is what we use out here for the Corsa. So, it would seem that it was a combination of #1- the wrong plug for a Contesta motor, #2 - Lean air/fuel mixture setting, #3 - Throwing on the C16 pipe with the Contesta motor produced way to high of rpm's for the motor causing way to much heat.

Would this sound like the correct diagnosis for this issue?

Having said that, I have ordered an MHR Rep which should be able to handle the Yasuni C16 pipe, correct? Also, what plug should be used with the MHR Rep?

THANKS!!!!!!!!

 

K, Here's the pics of the barrel. Let me know what you think. Also, what plug should I use with the new MHR Rep that shows up? Will the BR8EIX work on it?

Thanks!!!!

 

K, so I've got the MHR Rep installed, I'm still using the Arreche 19mm carb, now with a 105 main jet. I have a 24mm Arreche but haven't installed it yet. I'm wondering what I should be setting the 19mm carb at for ideal performance. I've got 3.8g rollers in now, 105 main jet, and A/F screw set to about 1.5 turns out. When it's idling it seems to sound fine, if I crank it to Wide Open Throttle real quick it boggs down. Also, I took it for a quick test spin, and I took it pretty easy, but it still seemed like it was held back or something. Not sure if its because it's really rich or not. I did as most suggested and added extra oil to the fuel. I still run the oil pump as opposed to premix. So would it seem like it's too rich of a mixture?

Thoughts?

Also, I've got a BR8HS plug in there now, is that the right one?

 

Ok, so I've got it all running now. It took a mix of (3)3.0's and (3)3.5's to get it running right. I've got the 105 main, and 105 pilot in there. It seems to be ok, but what RPM's should I be seeing? I took it out for a test run and it seemed like the power wasn't really kicking in until around 10,000+. I got it up to about 12,000-12,500 but then I slowed down in fear of blowing another motor. What range should I be looking to reach, and also how long can you maintain that high of an rpm? For instance if I'm using the bike as a daily rider, can I hold 12,000rpms for 5 mins or longer without worrying about it blowing?


Thanks a lot everyone!!!