Lifan 150 diffs and pics

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numroe

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Thanks to Ken and Linda at MSO I have been able to purchase a new Lifan 150 for my bike which is ready to ride - Saturday.

Some pics of it below. The most obvious differences are the right side cover (oil filter so no slinger), and the alum cylinder.

Some key things noticed about the stock Lifan 150:
* Stock cam has about 6.5mm of lift. Compared with Lifan 140 stock cam at about 5.4mm. Also the stock 150 cam has much fatter lobes - looking much like the Akunar A2 cam.
* Same head and case castings as in the 140.
* Rocker arms look identical.
* Oil filter is a a steel mesh (stock). I will seek a paper filter since I trust them much more.
* Much bigger CDI unit and coil. Different connector from the magneto too.
* Clutch pack looks identical to the 140 unit. 150 clutch feels the same thru the lever, so I guess the same springs - which will be too soft if the 150 stock can pump out the same torque as my 140 did with the A1 cam.
* Exhaust pipe needs a minor mod (shorten on the head end) so it clears the oil filter a little easier.
* Stock engine oil is "transport oil". Don't run on it.
* My valves were set right at 003 and 004. A nice sign of factory assembly care taken I hope.
* It sounds as loud as my 140 did with the A1 cam. So the 150 can breath ok.

Pics:

20080507-IMG_1471.jpg


20080507-IMG_1475.jpg


20080507-IMG_1466.jpg


20080507-IMG_1467.jpg
 
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More pics:

Oil fill access is ok:
20080507-IMG_1472.jpg


Ignition parts nicely tucked away here:
20080507-IMG_1469.jpg


Rider view of the new CDI:
20080507-IMG_1473.jpg


Flywheel:
20080505-IMG_1459.jpg
 
Get rid of that MSO magneto cover coz it just doesnt suit the engine!

Let us know how u find the 150 compared to the 140.
 
yeh cant wait for the review after the real ride on it noone around here realy has them or has any "knowledge " about them but ino you no your stuff so i cant wait

looks very sweet by the way
 
Seat has oil stains all over it.

Ken and Linda said the Honda TRX125 (older quad) oil filter fits.

I am sure it'll run just fine in stock form with my known setup OKO26.

As mentioned the stock cam is much more on the money, and the lighter spinning mass is easily to feel with a little throttle blip. It's real good to put a known carb setup on it. Due to work reasons, I'll only get one ride on it this month though.

Later on I'm keen to evaluate the engine with the Akunar A1 and A2 cams and also with a decent clean up of the head ports and using my Akunar valves. Akunar being what I bought for the value for the dollar. There are plenty of workshops near me who can tidy up the ports for me. Being a slightly bigger bore (same stroke) I'd expect the thing will breath a little better than the 140.

Long term Lifan 150 reliability is an unknown as yet, but having an oil filter plus a magnetic oil drain plug has to help.

For any guys with a stock Lifan 140 and thinking about it, I cannot more highly recommend the Akunar A1 cam. It's freaking amazing. It's also simple to drop a cam in, but because of the higher lift you must put in the Akunar springs too (about $25 for the 4 springs). If you do the springs, then the Akunar valves can go in as well ($20 for both), and when the valves are out, you can get some emery paper and sand the bigger bumps out of your ports. A new head gasket is about $1. You need stiffer clutch springs too (about $10) because the engine has so much torque. The cam is $55. Postage is about $15 for the lot. Unreal. My 140 case cracked only because of kick starting abuse. With the A1 you don't need to rev high, so the 140 engine will hack it no probs.
 
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The SR has a "proper" frame. Twin main tubes.

I'm onto the tyre situation. Pirelli MX scorp on the rear. Great in medium to hard. Not too bad in soft. On the front in the pics that's a Kenda milliville which is ok in soft/medium but not much good in anything else. Actually the Milliville is a fat front tyre and offers good rim protection which sometimes helps. For the front I also have a new Pirelli MX + new front wheel. But I need to buy the special disc bolts. New project but it'll have to wait.
 
Damn, I had a good test ride today ...

The right side clutch cover doesn't look so pretty any more. No crashing of significance, just the usual inside right boot rub. A polished alum cover would be more practical. No big deal.

The Lifan 150 engine:

I gave it a "hard" run in. About 15mins then cool down. Then another 40 mins then I changed the oil. Compression at the end of the day feels very good.

First oil drain appearance: No chunky metal parts. The usual run-in "shineys". The magnetic drain plug had a lot of filings on it. No cause for alarm assuming this is run-in wear and does not continue.

Gearing: I ran stock 15:39 for the first two rides, then 16:39 for the rest of the day (ie. about another 90 mins of giving it and myself a workout). Rode in 2nd and 3rd most of the time and it pulls the tall gearing with ease. In long bumpy straights I tapped it out in 4th and it gets along quite quickly. Almost scary fast in small woop type bumps.

The power: It's good. It spins up as fast as anyone riding in dirt would need in a pitbike. For typical off road pitbike use and riders up to about 85kg in weight, the stock 150 (with a good carb and exhaust setup) pumps about as much top end power as 90% (or more) of riders (like me) could use or need for cutting laps on technical tracks. IMO, most people would get far more gains (and fun) with suspension mods than seeking more top end grunt from a Lifan 150.

Power part 2: I think anyone only with experience with a stock Lifan 140 with an alum slinger will be blown away by this little 150 engine in stock form, since it would put out around 30% more torque right across the rev range! Yep, I put the 150 on the numroe offroad "feel dyno". ;) From my experience, I believe this output is mostly a result of the camshaft and not the extra 10cc. Any rider used to a 140 with steel slinger will think the 150 pumps out about 50% more torque than a stock 140, and it feels like that when accelerating, but it's not the case. Sorry but steel slingers and heavy flywheels just kill these bikes for MX style riding. Now, compared with a Lifan 140 with the Akunar A1 cam (now we're talking) I'd rate the stock 150 as having 20% less bottom end, 10% more mid range, and 30% to 35% more top end output. Still an overall gain. but ...

Power part 3: So that's a good wrap for this new engine, but personally I think it can be better. A lot better. Which means I will try mine (in June) with my Akunar A1 bottom end cam in it. Actually just my whole head off my 140 (better ports, valves and springs + the A1). The stock 150 has a nice smooth torque spread, but it is still a bit flat in the bottom end and surges into a meaty mid range. For faster laps it could use more bottom end because the Lifan engines have only 3 usable gears and they are spaced way way apart (ie. a 0.75 ratio change per gear if I remember right). So unless you want to fan your clutch all day to stay in the mid revs and above, you need more bottom end. I guess Lifan want dyno figures - because perception is everything in sales and marketing. But the lost top end with the A1 wont matter for most tracks. The extra 10cc (bigger pump) and bigger bore (better breathing) will still be there with the A1 cam. With the A1, the bottom end grunt on demand will be good for sure. I reckon the Lifan 150 will go from being great to being totally awesome - dude. :D

Gear shifting: Felt more positive and easy with the foot than my 140. But I don't know how typical my 140 is in the gear dept. I hit a false neutral about 3 times. Always when shifting in accel bumps. I'd clutch in again, click up firmly and no problems.

Starting: I was careful. No problems. The anti-kickback mechanism on the Lifan cam still plays up on occasion and lets the engine semi free-turn at times. But if gentle and persist then the piston will stop at TDC eventually.

Jetting: I had slighting throttle bog problems initially with my OKO26 which worked great on my 140. When trying to sort it out, I got a bit mislead, but eventually found I needed to only change the main jet. So I went from a K102 to a K105. Maybe this was needed because of the cam having more overlap than my A1. But probably because the seasons are changing and the air was cooler and dryer than my last time out. Very happy with my carb jetting today. I had so much fun!
 
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Its good to hear a review by someone that actually knows what they r talking about.

Thanks numroe, keep up the good work.
 
Great review. Glad you liked it. I found the same things with my bike but couldn't post that without sounding biased :) The new Lifan150 is the best out of the box engine around IMO. We tested the YX150 and the Lifan150 (both in SR's) on the same day and it was unanimous with our riders what the most preferred engine was. Once this motor is more widely available I think it will have many fans.

Cheers, Ken
 
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Tested my Lifan 150 again today, with the A1 cam in it (and Akunar valves and springs). Dropped on the whole head off my 140 actually.

Really nice engine now for what I am after!

If you want to blast down fire trails or MX straights, or maybe ride groomed BMX tracks all day with near infinite line options, then you might want to stick with the stock 150 cam which for sure has better top end HP than what I have now.

But if you want a super strong torque hit on demand, at the twist of the your right hand, in any shitty corner at any time (correct gear choice assumed), spewing dirt out the rear, then the A1 cam with beefy bottom end boost is a real good option. I just love it. Today on a rough, loamy rutted track, my 150 engine is now so much better than my skills or my bike's suspension and handling. I need to ride it much more, and maybe spend more $ on suspension.

Interesting to note that in stock form, the Lifan 150 clutch held fine. But with this A1 cam in, I am back into clutch slipping issues ... I can give it a little fan, and and then it'll never grab unless I ease off the throttle. So the torque peak with the A1 must be higher than what I had before. No probs though, For starters I dont need to fan the clutch often with this engine now, and secondly I have stiffer clutch springs and tougher fiber plates ready to drop in. Pitty I cannot ride again for another 4 weeks. :(

btw: I put a Pirelli MX scorpion front tyre on today. Supposed to excel in medium/hard terrain, but really good in medium soft. Must be a great all rounder. Impressive. Cost $60.

Next I must get a better chain, my KMC is so close to dying now. Poor thing gets hammered in good traction conditions.

Interesting today with the ruts being quite deep and the front disc carving badly in left hand ruts and pulling me off line. I cannot see any solution for this. Any ideas?

I also want to find a wider rear tyre than the usual 12" 80/100. On soft/medium terrain, especially loam, I just cannot imagine putting too much rear tyre on my bike. Anyone found a wider 12" rear tyre than the usual 80???
 
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My only criticism of the Lifan 150 is something I've mentioned before and the same applies the 140 and probably other Lifans, and I know the YX is similar ...

The wide ratio gear box is not ideal for MX track riding. Neglecting the stupid gap from 1st to 2nd (and neglecting 1st gear entirely). The gaps between 2,3 and 4 are too wide. About 0.75 difference per shift if I remember right.

Even with my new found spread of torque with the cam change, the gear ratios are too wide. It's a real shame. I'd guess this hurts laps time by up to 5 secs for a 60 sec lap.

Sure I could change my final drive gearing (sprockets) to make one corner perfect for some gear, but on a varied track that just means some other corner wont be right.

Lifan and their scooters ...
 
daytona paper filters fit the motor
Thanks. Who in Aus sells Daytona compatible paper oil filters? - Which will also work in my Lifan 150. My local honda dealer has no code/listing for a TRX125 filter part since "that quad was never sold in Aus".

I've been cleaning out the stock steal mesh filter, but would prefer paper disposable filters - if I can find any compatible part.
 

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