Hey guys, Im thinking im gonna make a little «review» about the athena 170cc big bore kit. Since there are little info of it on the internet, This review might help anyone considering to buy the 170cc.
My setup, This might or might not be the perfect setup to get the Athena kit to get maximum power.
Athena 170cc big bore kit,34mm mikuni flat side carb. 34mm inlet manifold. Unknown powerfilter.Gianelli exhaust ( The Athena exhaust is proboably better, But since the gianelli is a straight trough pipe with no restrictions in it I dont see any reason it wont let out enough exhaust to restrict the engine by much. If anyone has the 170cc with an Athena exhaust please tell me how yours is J )
So first, I want to just say some easy facts and lies about the kit.
Theres a lot of different opinions or rumors about this, Some say theres a godlike change in acceleration or top speed, I would say the ones saying this are braggers . There is a change in acceleration, maybe 1 second faster 0-100 acceleration time, max. Its not that noticeable to be honest.And im driving with a 17th tooth, maybe theres a bigger change in acceleration with the stock front sprocket.
And when it comes to top speed. It doesent feel like the Athena 170cc is as strong on the very highest rpms as the stock ones, It was windy when I tested my top speed,I did 80 mph, It shoots straight up to 75 very fast and easily, But then I have to gear up to 6th gear, and then it gets slower. Im shure I still can do 85mph. But it just feels like it takes longer time to get there. But as I said, was a windy day.
What I heard about the kit wich I find true is that its a lot stronger than the stock cylinder, With the Athena big bore kit you will never have to change gears because of a uphill. Im driving with a 17th sprocket. And the 170cc is so strong its just a dream to ride around normally with, Cause you can just chill around in 6th gear, Not thinking about the uphills or if you want to overtake someone, you just pull the throttle, You dont have to gear down to 5 or 4 to get enough rpm for the kick to get in, The power is just there waiting for you to release it !.Shure I could overtake without changing gears with the stock barrel too. But then it would take forever !.
But then when you want to play around some, This kit also gives a lot of fun !, Fast acceleration, Easy overtakes. Easy wheelies, With the 17th sprocket I can do wheelies in 1-2-3rd gear. In the 3rd gear im up in 45 mph when im wheeling.
When it comes to the power curve,Its a bit different. Cause its so much stronger than the stock one, if your driving in the 6th gear, You can get the power in about 40 mph, and at 50 mph it really starts pulling harder, And then it just pulls harder and harder until you reached top speed.
What I was impressed about the 170cc kit an what I was disappointed about.
What impressed me :
The power, I never have to gear down to overtake anyone, Even though it helps a bit, Its strong enough to overtake in the 6th gear by just giving some throttle. Almost no matter how fast your driving really. With some exeptions.
Acceleration. High rpm kick. I always heard its a low rpm cylinder, But the high rpm power is very impressive too .
Feels like driving a bigger bike.
The sound. Lovely sound of it .
The craftsmanship, When I first got the powervalve out of its package I though it was just 1 part, not two as the standard, It was so well crafted you cant really see where it splits.
And the head gasket wich follows I dont think ever gonna brake xD Everything seems top quality.
The fuel consummation, it doesent drink as much as I thought it would, I now done 140 km and still not on the reserve tank, And ive been driving it hard.
What disappointed me .
Well, as I said it feels like it doesent get to the top speed as quick as the stock barrel did. I dont know if it was the wind that day. But I have a feeling it wasnt.But really that doesnt matter at all, Because the acceleration is so fun, And the wheelies are so much easier, The overtakes are easier,
All in all, It was worth every coin.
If you want to have more fun doing wheelies, Easier overtakes, Faster accelerations, or just put it in the 6th gear and chill trough the roads. Then the Athena 170cc is for you, I am very pleased and its a good all-round kit. Good strength from the bottom if you want to just drive normally, And a lot of high rpm power if you want to have fun. And proboably has a lot of potential if your into modding like porting and stuff.
I changed the crank and bearings, Because the bearings and the crank was worn and had to be changed xD, I seized my stock barrel 3 times i think and i think that the bearings and crank was the reason for atleast one of the seizings xD
If your crank and bearings is in good condition you wont have to change to a improved crank or anything, but if your bike has done alot of miles like mine, I reccomend changing the crank and bearings ;)
I'd agree with you on some things. From my setup: DEP front, Big one end. 38mm Flat slide carb. Snorkel out and airbox drilled out to increase air intake. All derestrictions done on 2001 bike.
Bike did 90+ (Indicated)
Pissed away all the fuel (Probably the carb to be fair)
And power wheelied (No power valve fitted)
Didn't have the power valve on it so not sure how it rode normally. Without it it would chug along but you really needed to be in the powerband.
1000 miles to run the top in. Varying the speed and throttle control every 100 or so miles.
Very low RPM useage in the first 100. Always letting it warm up first.
Low RPM useage the next 100
Mid RPM useage for the next 200
Varying RPM useage from very low to mid high for the next 200.
Varying RPM useage from low to high put not for prolong periods at high RPM.
Should be fine if you follow that procedure and always warm it up properly. Make sure you use mineral oils to start with mind!!!!
Fully synthetic once the break in procedure has been completed. I'd say for low to medium rpm useage continue with mineral oils changing to semi synthetic from there on up. Then fully synthetic afterwards.
The reason for mineral oils is to wear any imperfections in the barrel. It's quite important that the mineral oil is used.
Sounds nice m8, Im shure mine can do 90 too. Why dont you have the 170cc anymore ?
Siezed. Bottom end gave way after a few thousand. It was just too much strain for such an old engine. The 170cc kit survived mind. Just needed a new piston for it. In the end I rebuilt the bottom end and sold the bike with the Athena barrel and bought an RE and an RS125. The Athena just changed its accelleration really and the RS125 was quicker overall than the 170cc. That now has a 160cc Polini Kit on it which just makes the RE look like a 50. But the rs is a fair weather bike. The RE is for everyday smashing about.
Well. I dont know about the english kilometer. But 50 000 norwegian kilometers. 1 km is 1000 meters .
That cyllinder got a good running in, Cause the pv was a bit adjusted to not open properly. So it wasnt forced anything untill i got it run in properly ;)
Well your not supposed to force the engine anything in the break in period, And mine was certainly not forced anything because it couldnt be forced :P,
I didnt know it was adjusted to never open all the way :P
Well your not supposed to force the engine anything in the break in period, And mine was certainly not forced anything because it couldnt be forced :P,
I didnt know it was adjusted to never open all the way :P
Well because the engine is natrually aspirated, the two stroke boost aids the engine and therefore less strain. If you keep the powervalve shut you will gain bottom end at less work. You have to restrict the throttle manually. But of course you know this.
no servo m8 have my servo unplugged at the moment just trying to get some authentic new pully cables before i try again with that.
i have my alignment mark set about 0.5cm infront of the notch, to the front of the bike aswell to get the valve fully open (same case with my both my 125 cylinders too) no sorry i stand corrected there it all lines up on the 125 barrel i have apart right now
wierd how its not open fully on the notch cos yamaha must know something we dont here
or is it just a restriction
-- Edited by tripr on Wednesday 11th of April 2012 08:49:48 PM
Ok, Today i tested top speed again, had 86 according to the speedo. wich is the fastest the speedo go. But after i got to 86, i know the acceleration didnt stop ^^ but idk how fast i went, gotta get a car or a speedo behind sometime.
why is that then the pv alignment is set as per manual with the notch but doesnt sit the valve flat open in the exhaust chamber its still shut off a bit
Ehm, If you put the adjustor to have the hole paralell with the notch behind on the housing for the adjustor, It doesent open completely. I think, That is why i have set my adjustor about 0,5 cm to the left.
its not hard really, Just play with the adjustor abit, Find out where to put it to make it go faster ;)
thinking about geting one for my yz but unsure yet as im running pinned powervalveand dont have a servo do u think it wud be safe torun pinned on a 170 kit?
i do m8 ran mine pinned for around 3000km so far it runs an sounds lovley even the mot mechanic an my instructor commented on how nice my bike sounds but id only buy one if you can get your hands on a cheap one. not worth full price at all for the difference it makes but still good to have one in my opinion
-- Edited by tripr on Saturday 14th of April 2012 08:42:22 PM
cheers, im starting an engine from scratch so i think il invest in the aftermarketcrank etc and a fue other things to get the most out of it and run it safely without worrying about it blowing up
your review is more or less spot on nordt,i run a 18/55 gearing and it still pulls hard from the bottom,wheelie in 2nd gear with a slight tug on the bars and not really much difference in top speed but its the way it gets there that impressed me,much more linear power and like you said will accelerate in 6th gear for better overtaking not having to change down,and sounds very nice with my full dep,also having a strong bottom end/crank is crucial or she will blow!!
monfooldrop, What crank are you using ?. I just got a new stock crank. Thinking yamaha made them strong enough. Since there is no more rpm, And proboably no more than 30 bhp, ( wich is only 5-10 bhp more than running with only a gianelli or dep exhaust ).
And its only 36 cc extra from what i used to with my 1,5mm overbore.
I am running with a 16 sprocket on the front now, And a stock one on the rear. i noticed a change in acceleration, it accelerates really quick up to top speed, Noticably quicker than with the 17 sprocket, But i actually think wheelies now are less fun, and in the 3rd gear i cant get the front wheel all the way up.. Dont know why but with the 17 sprocket i could.
Im gonna change the sprocket to 17 again and test the difference in acceleration, And try some more wheelies with the 16 sprocket, And evaluate wich i like the most. Being able to do high speed wheelies, Drive faster with less rpm. Or Accelerate a bit faste, but have to wheelie slower. And have to have higher rpm all the time ..
I really think im gonna go for the 17 sprocket again, Since even with that, It still accelerates better after 100 kmh / 60 mph than with the standar barrel.
but with the 16 sprocket the bike feels like it accelerates so much faster after 60 mph too xD. This is gonna be a hard decision xD its so fun to be able to reach top speed in no time at all :P.
But for some reason i felt i could wheelie easier in 3rd with the 17 sprocket than with the 16 :S