90 engine choices?

[Eckchaz]

I'm looking for a 90 engine and was getting confused about the options until I came across this http://www.rcheliaddict.co.uk/engine...e-engines.html

It only really told me to stay away from the pumped versions as O.S had crappy pumps on its earlier models and people had problems. This thread is just over a year old now so I'd though about a little more clarification on them and a little update (if any)

I came across a few posts recommending the YS91 SRS with the Hatori SB19 as a great combo but just want to look at my O.S options as I'm not a hardcore flyer.

Am I right to presume that all the O.S have the same power? Also, am I right to think the 91HZ (18600) is the basic like a OS55H on a bigger scale?

And then theres the pumped 91HZ-PS (18620) and then a 91HZ-R (18640), whats the "R" regulated version.. in terms off how it works compared to the pumped version? and is the "R" simular to the YS-SRS??

And lastly (sorry again for all the questions!) is the Hatori SB20 the best muffler for a O.S?

[sacko]

OS91 HZ and HAtori SB20 will be a good combo.

There is anothe pipe (maybe the 939) for OS engine.

[Eckchaz]

Thanks Paul.. Is that what your using on you Srimok?

[sacko]

Yup, my pipe is the 939.

It is super smooth

[Eckchaz]

Yup, my pipe is the 939.

It is super smooth

Paul, you have to stop teasing me with the pics!! Just a few more weeks!! Unless a 50 size comes out...

So do you know what the "R" means?

[sacko]

Its regulateed like the YS91, which is exactly the same engine as the HZ it just has a different way of adding pressure to the tank.

Either will be fine.

[chugga-bug]

My vote goes to the YS91srs. If it's 'only' as good as the SR, then that'll do for me. Smooth as silk, easy to tune, and sensible spares prices.

[Sao]

The r is for regulated, it work just like the YS engines, instead of a pump or using muffler pressure it works off of crankcase pressure with a pressure feed coming off the back of the crankcase and then it's regulated as it goes into the carb.
O.S have finally seen the light and used the same method as YS and done away with the shonky pumps.
I'd go for the YS personally.

[Eckchaz]

Thanks for explaining Sao!

I've literatley just been offered a new HZ for a very decent price... now is it really worth me paying over £100 more for the SRS now?? Bearing in mind I'm only just attempting bits of 3D and probably going to be a while before I get there?

[sacko]

Personally I wouldnt buy a secondhand engine. If I knew its history and knew the owner I would be tempted, but buying second hand engines is more hassle than it is worth.

If it is only £100 more to get a spanking new SRS with a years warrenty, compared to the secondhand OS without warrenty.. I wouldnt hesitate.

Buy once, buy right

[Kwickkwack]

It may have escaped your notice Paul


But someones nicked half your heli

[Eckchaz]

Personally I wouldnt buy a secondhand engine. If I knew its history and knew the owner I would be tempted, but buying second hand engines is more hassle than it is worth.

If it is only £100 more to get a spanking new SRS with a years warrenty, compared to the secondhand OS without warrenty.. I wouldnt hesitate.

Buy once, buy right

I know mate.. I adopt the same motto..

The engines from a fellow forum member and states its brand new and unused

[MartinH]

It may have escaped your notice Paul


But someones nicked half your heli

No blades was the big give away for me :/.

[chris jones2.4]

theres a ys 91sr on bmfa with two exhausts, heres a linky The BMFA Classified Ads Service / YS91SR + Exhausts