Somebody slap me!! 90 2 str or 70 4 str

[scoota]

Hi Ausfishers,

Posted some time ago about repowering a Seafarer v-sea 4.7m and was keen on a 60 yammie 4 stroke high thrust but procrastination drove me mad and reading other posts I decided to go the biggest motor with lightest weight and settled on buying a Yammie 90 2 stroke at the upcoming boat show.
Time waiting can be a nasty thing:-?
I can get the 70 4 stroke Yammie for around the same dollars!!
Are they the unbelievable new technology from outerspace as Yamaha recon or is it just hype over a highly modified 1 litre motor that could have a short life expectancy and reliability problems?
Very keen on the 90 but would like some feedback on the 70?
Dealers are selling the new Cruisecraft 485 with the 70 as the standard motor and the Cruisecraft is alot heavier than my Seafarer.
Ease my mind and tell me the 90 is the ducks guts;)

Scoota...

[FNQCairns]

Hi Ausfishers,

Posted some time ago about repowering a Seafarer v-sea 4.7m and was keen on a 60 yammie 4 stroke high thrust but procrastination drove me mad and reading other posts I decided to go the biggest motor with lightest weight and settled on buying a Yammie 90 2 stroke at the upcoming boat show.
Time waiting can be a nasty thing:-?
I can get the 70 4 stroke Yammie for around the same dollars!!
Are they the unbelievable new technology from outerspace as Yamaha recon or is it just hype over a highly modified 1 litre motor that could have a short life expectancy and reliability problems?
Very keen on the 90 but would like some feedback on the 70?
Dealers are selling the new Cruisecraft 485 with the 70 as the standard motor and the Cruisecraft is alot heavier than my Seafarer.
Ease mind my and tell me the 90 is the ducks guts;)

Scoota...

The 90 is the best choice purely as an engine, what is your style? how many people will travel with you, how often do you boat, ski/tube, how far is your average trip out . Can you handle cruising 10km/h faster. If to get the best out of the boat can you deal with using $20 more fuel per $100 ( better again if you drive it like it's the 70 4 stroke).

Buying 2 stroke oil, the extra noise, vibration, harshness...the better engine doesn't come without it's rougher aspects.

50 4 stroke will plane it, a fishing boat doesn't need much more than that but the owner might.

I too would choose the 90 to get the best out of the boat...but I travel up to 140km in a days fishing, if i was only doing 50km in any day, I too could consider the 70.

This is the 4st engine those two fishing blokes fitted to their boats, one bloke fitted it to a heavy tinny, couldn't see anything spectacular when they raced it on TV, hole shot, nothing.

Any other brands of 70-90 4st in the offering??

[scoota]

Old motor was 100kg 70hp Jono so was looking for something around the same weight up to a max of 125kg. Both these motors are 120kg.
All other makes of 4 strokes and 2 strokes including DI's 75hp plus are 20-50kg heavier than these two options.
Could have up to 4 pob fishing the bay and creeks or 2 pob fishing offshore 20-30 mile.

Scoota...

[FNQCairns]

Scoota what was your thoughts on the old motors ability to push the boat?? If it was fine for your needs then the 4stroke 70 will be a very welcome upgrade, if it was a let down performance wise than the 90 is the choice.

Plan to own at least 2 props to get the best out of the 70,just like the old 70.

[kitty_cat]

hey mate
how big is your fuel tank
the 4 stroke will give you 40% extra range allowing you to explore offshore abit more .
if resale is also a thought a v sea with a 4 stroke sells very well

wayne

[Jarrah Jack]

You've got all the answers there, the extra range can be a big plus with the four stroke as I'm finding out with my 70. i had a choice of a 90 2 stroke at the same price as well. Being more conservative minded I went with the 70 and am happy with it on a similiar weight boat. The quietness of a four stroke I think is handy in some fishing situations where fish are easily spooked.

You'll get a good motor for your needs whatever you choose so the question becomes more of a gut feel for the type of boat you want / person you are / boating you will be doing and if you intend to sell it soon.

[Noelm]

4 people in a Vsea will be cosy, and a 70 will be pushed with that sort of load, this si one of those toss of the coin things, either motor will be fine, extra HP is always handy, but then it is possible that the 4 stroke is lighter on fuel than the carby 90, so, less fuel needs to becarried in the first place, making the boat lighter for the same trip.

[ahamay]

I was in a similar situation recently with my new boat with approx the same weight. The 70 was still about 2 months away so I was choosing between the 60 4 and the 90 2.

Ended up with the 60 as I wanted good fuel economy, no smoke, quiet as well as I could not be stuffed with maintaining oil levels again.

The 90 will rip with the standard SS prop, but it will probably rip a bigger hole in your wallet as well.

I opted to knock off the speed for the petrol savings. I kept saying EFI or carby and went EFI every time.

The 4 stroke is a hell of a lot quieter to flush on the hose at home as well.

[svranjic]

I am in a similar position right now. Trying to decide what to power my 4.7m glass boat with.

I dunno if this helps but my train of thought was if you cant carry heaps of fuel on board and/ or dont intend going too far out then I guess the 90hp 2 stroke yammie suits you.

If you cant hold massive amounts of fuel onboard and want to be able to venture out and benefit from low noise, smell and first turn start then the 4 strokes are the go.

But then thats not considering the direct injection 2 strokes, which are alot heavier but offer benefits of both worlds.

Its a hard one....... I have had a keen eye on the yammie 60hp 4 stroke as well as the 70hp 4 stroke. But Im not sure how a 60 4 stroke is going to perform on a boat this size and weight. A 4.7m boat really limits your choices due to the weight factor. Nothing worse than having a boat with its bum right in the water.

Go the 4 stroke I recon....... if not the 4 then direct injection 2 stroke depending on the cost.

[deckie]

For that size hull if u can whack the 90 on it i;d do it. Would not go any higher than 125kg tho at all. Even the 70 stk at 105kg might be a good option...that motor would marry well with that hull but seems u carry lots of weight.

No subsitute for torque.

Why people giveashyt about things like noise and smoke i have no idea. They'll happily wander down George St sity at lunchtime and suck up ten times the fumes without any worries.

A 90 will just murder it up out of the hole for stop start surface school chasing whilst the 4 stroke 70 will always seem a bit of an effort.

Burn a bit more fuel...why the hell not u work hard and u want some fun. Lucky if its 10-15 bux a trip.

Dont forget that a mid range 2 stroke always seems to get more frugal on petrol as it ages...no idea why. All tests compare new motors consumption but all mature 2 strokes i've had have been kinda good on the gas. They smoke far less than they used to and any resale value is offset by savings on servicing and purchase price.

If i saw a second hand vsea with a 90 2stoke or a 70 4stk second hand i;d take the 2 stoke all day long. Great hulls when not overloaded at the rear...but having 4 onboard is a bit too damn chummy for my liking. If thats common use the 90 and keep them away from the arse of it.

[Wayne_Red]

I was talking to a dealer at the Sydney boat show last weekend about the new 70 yam4s and asked him if he had on out yet. He said they took off a 70 2s yam and fitted the new 70 4s on one of those southwind banana boats that were around a few years ago. He said they were amazed at it performance over the 2s, he said it out performed it in every way, hole shot top speed etc. He was quite impresed and suprised. he said a ball park price was @10 1/2k
Although I like the 90's on vc's (my brother had one on his for years and I had other mates who had 70's on there vc's) the new 70 might be worth a close look.

[deckie]

I was talking to a dealer at the Sydney boat show last weekend about the new 70 yam4s and asked him if he had on out yet. He said they took off a 70 2s yam and fitted the new 70 4s on one of those southwind banana boats that were around a few years ago. He said they were amazed at it performance over the 2s, he said it out performed it in every way, hole shot top speed etc. He was quite impresed and suprised. he said a ball park price was @10 1/2k
Although I like the 90's on vc's (my brother had one on his for years and I had other mates who had 70's on there vc's) the new 70 might be worth a close look.
Well he would...wouldnt he.
Reality might be a little different tho.
They flog as many 4 stks as they can these days and arnt ashamed to bullshit you...and of course they want to service them for you at no small expense.

If we ask "how's the performance compared to the equivalent 2 stk ? "... what are they likely to tell us ?

Test drive anything..dont listen to salesmen.

[DALEPRICE]

gday scotta,

simple answer,

90 2 stroker will have a bit more zing about it for sure,
4 banger will have you over the moon with economy, but a bit slower than
the 2 stroke.

i had a 60hp high thrust on a yamaha long boat and was an awesome little motor. what it pushed was amazing.

cheers dale

you getting any fish at the moment at cw ?

[dreemon]

I've got the carbed yam 90 2st and if I had to ever replace it I could never go to a lower hp, noise and fumes ? more people tell me how quiet it is and its easy to talk at the helm at any speed, only a bit of smoke at first start up at the ramp and thats cause I choke crist out of it to get it fueled/oiled when it's cold , even at 6 knot zones it's very minimal,
you'll have heaps more fun with the 90 for sure, but it wouldn't stop me from driving it if it had lower hp cheers

[murf]

Hi Ausfishers,

Posted some time ago about repowering a Seafarer v-sea 4.7m and was keen on a 60 yammie 4 stroke high thrust but procrastination drove me mad and reading other posts I decided to go the biggest motor with lightest weight and settled on buying a Yammie 90 2 stroke at the upcoming boat show.
Time waiting can be a nasty thing:-?
I can get the 70 4 stroke Yammie for around the same dollars!!
Are they the unbelievable new technology from outerspace as Yamaha recon or is it just hype over a highly modified 1 litre motor that could have a short life expectancy and reliability problems?
Very keen on the 90 but would like some feedback on the 70?
Dealers are selling the new Cruisecraft 485 with the 70 as the standard motor and the Cruisecraft is alot heavier than my Seafarer.
Ease my mind and tell me the 90 is the ducks guts;)

Scoota...

how fast do you want to go??????????????

there are heaps of people around hear at Coffs with V-seas with Craigs having the heaviest motor being a 80 4str yam and it flies, got a 120 hrs on it now and he is stoked

its an overkill though on HP as he will never be able to use it around here, maybe you do more calm water work? or skiing?

if you travel up to 100km in a trip then the 2str will be heavier than the 4str by all the extra fuel you will have to carry

Craig has approx halved his fuel consumption with the 80 4str from a 70 2 str so the 70 4str will be sweet as

again are you in high speed bass comps :P doing a lot of skiing? or just mad and want more speed and power ho ho ho :)

cheers Murf

[Giffo65]

I have a 2007 EFI 60hp 4 stroke Yammy High Thrust, on a 4.5m Polycraft CC (Hull weight is about 400kg with the CC).It replaced a 50 hp 2 st Yammy,The fuel saving, less noise and no smoke are great.You are concerned about longevity with the 4 stroke,mine has 2100 hrs on it and still going strong.Buy the 4 stroke !!!!!!!!.

[murf]

I have a 2007 EFI 60hp 4 stroke Yammy High Thrust, on a 4.5m Polycraft CC (Hull weight is about 400kg with the CC).It replaced a 50 hp 2 st Yammy,The fuel saving, less noise and no smoke are great.You are concerned about longevity with the 4 stroke,mine has 2100 hrs on it and still going strong.Buy the 4 stroke !!!!!!!!.

2100hrs :o

thats great because mine only has 1780hrs, I have heaps left ;D

and out of the 14 internal combustion motors I have on the Farm the 4 stoke outboard is the easiest to service, don't have to even bend over to change the oil ;)

bloody cost me $35 bucks the other month to change the timing belt too :-[

cheers Murf

[Wayne_Red]

Well he would...wouldnt he.
Reality might be a little different tho.
They flog as many 4 stks as they can these days and arnt ashamed to bullshit you...and of course they want to service them for you at no small expense.

If we ask "how's the performance compared to the equivalent 2 stk ? "... what are they likely to tell us ?

Test drive anything..dont listen to salesmen.

Don't shoot the messenger, the question was asked of any experience of the 70 4s yam. I related a simple question asked of dealer at the boat show, he wasn't trying to sell me one and I wasn't looking at buying one. My point was, he himself was impressed and IMO if someone is looking to upgrade the new technology the 70 has is definitely worth taking a serious look at.
Another question, for point of interest, was asked of another yam dealer what the new release 225 was like compared to the old 225, his reponse was "the new one sh*#ts all over the old one for power
Seems to me like the new technology is not to be discarded lightly.
Wayne