YakMad

When you go to a higher Nitro fuel you need to not only re-adjust the high end needle but you must also richen the low end (idle) needle slightly as well. I've been running smaller ASP fourstrokes (.61's) on 20% for a few years and they seem to perform well on it, some power gain but what I really like is how much smoother they run now. I use 20% alot as I have many smaller Saito engines which really perform best with high nitro fuels. I have found that bigger two and fourstrokes .91 and bigger prefer lower nitro fuels. I can't see how 10% fuel would add to the wear on any engine that was running well on it. I have not used less than 10% nitro fuel for many years and have not had any increased wear and I fly every flyable weekend and I am not known for my conservative use of the throttle.

I agree I never use the idler solution and have never had any problems with wear on the servo output shaft but always use good quality ballraced servos on the rudder.

How could anyone improve on the Projetti??????? I have one for years that started out with a cheap 400 brushed motor and moved on to a brushless set-up with cheap 3s lipos and it still flys on rails. The Scimitar looks interesting but looks like it may need a smooth hard strip, doesn't look like it could be hand launched and I am sorry it is way too expensive for a foam model.

Gaz,     I would suggest using the OS silencer to break it in as it will rule out any potenial problem that an after market exhaust could create. I know fourstroke are not sensitive to exhaust back pressures but sometimes the pitts type mufflers can create problems when there was none, not saying this will happen to this engine but at least if it's run in on its own exhaust you know the engine is running well before you change mufflers. The engine you have does not need exhaust pressure as it has a pump, just follow the OS instructions on how to plumb the tank.

Sounds like it could be a stuck valve but like BEB I am not a YS person either, this should be easy to check by removing the rocker covers and check if either valve sping is stuck open or if the either valve is tight by push the valve down by hand (by finger) and feel for any tightness.

Watering can?

15x8 always seemed to be the best prop for the ASP 120 fs, the model comes with a plastic spinner which to be honest is rubbish, I never use plastic spinners with fourstokes as I found they always manage to get thrown by the engines.  

I use a self tapper thru the plastic clips as I had a wing move in flight which could have ended badly, the problem may be solved on the latest version as mine is an early example.Edited By David Ashby - RCME Admin on 11/11/2011 13:43:47

As I said I am a fan of ASP engines as once run in they are pretty much faultless (apart from the odd leaky needle valve) just not as powerful as an OS (overpriced) or a Saito (also gone very pricey). I have or had most of their four strokes from .61 to 1.80, my favourite is an old .91 FS which has never missed a beat in four years of service. Seagull have a habit of understating the recommended engine size but if you are just doing scale aerobatics and not expecting rapid climb-outs heading for the clouds the 120 should be OK, the Saito 150 I had in mine was really a bit too powerful for it but that's what the throttle stick is for and it would fly around on half throttle with this engine.

Futaba 3010 are only rated at 5 kg torgue at 4.8 volts not really enough for a large model, plus you are running a petrol engine up front, which you really need to use metal geared servos as the vibration from a petrol engine can damage plastic geared servos. I always use Hitec 645MG servos (7.7 KG at 4.8 volts) with a battery capacity of at least 3300 mah or bigger, Sub C type cells or a 2S lipo pack of the same capacity in large models.

Phil,     It should be OK for scale aerobatics, it has a fairly big wing but just remember that it's a big airframe, if you can get a look at one in the flesh first to give you some idea of the size.

Phil,     I had one for a while, I used Hitec 645 metal geared servos with 7 kg torque with a Saito 150 up front which to be honest was a bit too much power for it but I would still recommend a powerful 120 if you intend to do aerobatics with it, although I am a fan of ASP engines I have found that the 120 is not the most powerful around and may not suit this model. For a Decathlon it has no real vices just watch out for the powerful rudder as the fuz is short, too much rudder can get you in too trouble.

What prop were you using on the ASP .61 fs, I have several and found APC 11x7 on 12% nitro or APC 11x8 or 12x6 on 20% to suit them best. Are you still using Optifuel?. They do take a long time to run in so don't rush it, I have 3 in the smaller Kyosho Warbirds which all perform very well and have given years of service, I think you have seen my models flying, if you are still using Optifuel I would go the 20% nitro.

Ben,   You don't have to mount the remote needle on the rear of the engine, you could just screw it with some packing behind it directly to the firewall, I did this on a small delta as I needed the engine mount as close to the firewall as possible, it's been working fine this way for years.

Check-out the FrSky Hack module 2.4 conversion, I convert an old Field Force 7 to 2.4 some time ago and it works perfectly, GiantCod and others stock them, I think it only cost about £24 for the module and 8 channel rx at the time. There is a little bit of soldering involved but only 3 wires as far as I remember. Edited By YakMad on 07/10/2011 08:36:06

I always used a APC 15x6 prop on the two Saito 100's I had.

It's not a model a more

Those Magnificent Men and their Flying machines, they go up, dee, dee, dee, they go down, dee, dee, downnnnnn...........

I know the owner of the YT KI-84 would not be happy with his model being mistaken for a Zero! It's a Seagull Edge 540 72 inch wingspan going in behind him, thats the very right hand end of my local patch, the photo was taken from the pits area. Get your coat Dorest Flyer Edited By YakMad on 09/09/2011 09:23:16

Windsurfing, Kitesurfing and Stand-up paddle boarding.

Puffin Models also do the MEGA range which are inrunners which would be better for a small plyon racer, the smaller sizes are a direct replacement for 400 brushed motors but with alot more power of course, give John a shout, I've been using them for years in small fast models, never missed a beat.

After lining the cowl up and drilling the mounting holes I glue half of a furry mylar hinge (CA hinges) over the hole on the inside of cowl using CA glue and re-drill thru the now hard CA hinge, it's also a good method to repair enlarged mounting holes, I also use silicone washers (Maplins stock them) on the mounting screws.

Good news..

BEB,     I had one of those when they came out first, good flier, mine had a Saito 72 in it, could have done with the 82, I just used ply doublers on the engine box and firewall, the only weak area is the landing gear mount as there is little supporting structure, try to beef it up before flying if you can to save on future repairs.

Peter,     Good to hear you have you're 180 back, it's interesting that they said the valve timing was off. I do all my own maintenance on my Saito's. I purchased a Saito 100 in the US when on holiday one year but the engine was a pig to start, I decided to strip the engine to see if there was a problem but could find none, after re-builing it and setting the cam gear timing correctly (piston top dead centre and dot on timing gear facing straight down) the engine started first time and never missed a beat, the only conclusion I could come to at the time was that the valve timing was off.