Avenger 15Occ 16Hp RACE Engine complete!

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im loving the look of the lifan 150
especially that the side seems to be a replica of a take clutch cover
do they have replacement oil filters yet?
 
guys my 140 pulled 17.19hp on the dyno at work @14,750rpm after the kitaco irk was installed with the big race cam and ported and polished big valve head on it here is a dyno slip of it, it is a old dyno so it doesnt have torque reading
mybikedyno140cckit.jpg
 
how fast would your bike go seduce on a straight on dirt and road rufferly
 
guys my 140 pulled 17.19hp on the dyno at work @14,750rpm after the kitaco irk was installed with the big race cam and ported and polished big valve head on it here is a dyno slip of it, it is a old dyno so it doesnt have torque reading
Sweet!
What Carb??Jetting??What racecam??
 
Today I was thinking that maybe I didn't need this engine. My son will be using the bike now and he doesn't need the extra power and the electric start on the current engine will be easier for him.

Well I took him on a ride to show him how to use the clutch and gears etc. When we finished I went on a quick ride. I went about 50 meters and heard a noise from the engine. I stopped and looked down and oil was pissing out. I thought I may have hit a rock, but the hole looks like something from inside has shot out. Oh well, I need the new engine now. Especially after we rode it around with no oil for a while :D
 
I am running a 7.1 mm race cam and a rejetted 28mm keihein
alot of fine tunning has been done on this bike and pulls f en hard
 
Engine arrived today, it is a bit different to my old one but it fits. When I tried to start it, I kicked it over a few times and then the kicker slipped and didn't return to position. I'm ecstatic that I am now going to have to open the engine, man it makes me so happy. :mad: I hope someone steals it tonight. I might leave it out the front.
 
Sorry, only problem with engine was the guy using it, kick start gears are fine. Tip to self, when tired stop working and go to bed :rolleyes:
 
I had a short ride with the new engine today. It is a hell of a lot better than the old 125 FYM Motor. It sounds pretty tough and is very responsive. It accelerates hard and gets to the peak quickly (doesn't feel like it is having trouble winding up and I'm 90 kg). I must say a wiring diagram would have been helpful in the package. It also is a little hard to start, but I am guessing that the combo of new engine and the slight exhaust leak may be to blame.

Also it has to be said that when I thought I had issues, they were very helpful and offered to swap the motor over or supply parts (depending on if I wanted to pay freight to send the motor back).

Hopefully I will get a chance to give it a real tryout over the weekend.
 
get a video of how the bike goes at top gear top throttle

I will try to remember this weekend, remember this is in a quad: Elstar FYM Typhoon : es125fym. I'll show a comparison between it and my banshee... wait that may not be fair :). Actually it may compare pretty well to my mates Polaris 250 now, the old 125 engine was just a bit slower (10KM/H). The Polaris is massively restricted by the stock exhaust though, it is about 22 HP, but it is heavy as hell.

The irk certainly changes the way the engine works. It peaks early but seems to have little acceleration at the top revs. It was pretty hard to start so I messed with the irk and it seems better now. The irk was not set in the middle, it was set at one end. Which way to advance and retard? I just set it in the middle and it is easier to start.
 
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Down (clockwise) advances and up (counter clockwise) retards .....

Sounds a lot better now ... 11 RWHP (12.3 with a decent stepped header pipe) is not to be sneezed at for $500 + postage ........ Does your engine rev cleanly from off idle to peak ?????? The dyno report shows how bigger carbs can typically bog and lose power in comparison to a smaller carb .... you can clearly see that it's due to a sudden vacuum drop (and therefore fuel delivery) as the throttle is opened .......... whereas smaller or oval bore carbs maintain velocity and vacuum until the revs are underway ........ The engine actually picks up 1/2 a HP up top with the 22 mm carb .. The 26 mm Molkt would work better with jetting and sorting . Smaller carbs are less sensitive to bad jetting since air velocity is higher with a stronger vacuum signal (the factors which carbs rely on to function correctly) .... so they are both are more constant and consistent throughout the entire rev range ....... a larger pilot would most likely correct the midrange stumble ......

It'll be the IRK making it a bit harder to start ...... you have to kick it as hard and fast as you can from just after TDC on the power stroke .... Does it kick back ? If so you have the timing too advanced at idle ......

The top end drop off is the cam running out of breathing ability .......

Overall those engines are great if you respect their mechanical limits in their stock form ...... like ANY motor ... :)

dynoyx150.jpg
 
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It did rev cleanly, I had a problem with the irk. One of the three plates fell out. They are sending a replacement and are apparently fixing the problem at it's source for the future engines.

I took it out on the weekend and it ran pretty well, I did a dodgy job with the clutch that caused a couple of issues, but a new clutch cable is on it's way. I raced it with the banshee and apparently it held top speed with mid/high fourth gear on the banshee (the banshee has 6 gears and goes about 120km/h), of course it didn't have the acceleration of the banshee, he had to take it easy getting up to fourth so I could stay with him.

We took some video, but the really good stuff we took (full speed racing past camera) was being taped after the tape ran out - hey you can't choose brother in laws either :D . He is gonna send me what we have and I will post it if any of it is any good and we will make another one soon - with tape and all.
 
le/garage is rite they only make between 9 and 12 horse power and id rather own a 140cc yx 1p56fjm and bore it out but i only want around 15 - 16 hp so y have the excess
 
so what do use rekon these motors are worth buying or jsut stick with lifan.
 

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