Nickmind

iTrader: (5)

Hi all,

I am trying to tune my Hyper .21, that I have not used in over a year. After my last run, i took apart my buggy and engine as well with the carb.

I set the needles to the break-in settings in the manual (5 turns out for HSN, 3.5 for LSN, and flash for the mid-range). It is very hard to start, and when it does start, i give a little throttle and stalls.

1. Just to clarify that 5 turns and 3.5 turns in the Hyper .21 manual, does mean 5 and 3.5 - 360° turns, Not 180° turns, correct? Seems like a lot of turns out for both.

2. I think a part of my problem is my mid-range needle. So I took off the HSN housing, and looked into the hole. The mid-range needle hole was not in the center at all. So I set the mid-range needle so i can see the needle hole in the middle of the HSN housing hole (but not in the center), and is still flush to the carb body. This is what my carb looks like now:


Is this a normal setting?

3. I also put on a new fuel flirter from Yeah Racing, I see fuel passing, but I do see air bubbles in the filter. Could this be my problem?

Thanks for your time and help.

GHETTOTEACHER

Your factory setting are about right. Start there then start leaning it out for performance. I use the rule of flush. Flush with the HSN, LSN and do not touch the midrange. Keep the mid just about flush to the outside houseing.
Hyper carbs are not known for holding a tune. Thats why people switch them out with OS VZ series carbs.

1 turn= 1 full rotation of the needle. one 360 degree= 1 turn
Mark your screw driver for tuning.

Bubbles in your fuel filter means nothing.

Hope this helps!

Nickmind

iTrader: (5)

I got the baseline setting from OFNA, the settings in the manual are way off. basically they are flush settings, thanks for that. But what do you mean about the carb? Are the needles walking in the carb? How does any carb not hold a tune?


Thanks for your reply.

GHETTOTEACHER

The Ofna block is a great engine, but the carb could not hold a constant tune. The carb was made of plastic and when the engine got up to temp, they seemed to lean out and send the temps up. I remember when I had one I had to constantly keep tabs on the low speed and high. I swapped out that carb with a OS VG carb and it was constant set and forgett it! All metal construction and two needles. I liked the Ofna motor because it was a Hyper 8 and it has crazy RPM's.
Many people have the same complaint. They all switched the carbs and everything works great.
Motors like OS are more tune friendly.