nheather

I've just replaced a troublesome engine on my son's hyper 7. The new one appears to be running more consitently though I haven't got it set right just yet. One thing that seems odd, but I can't quite remember how it was before. At what point should the clutch engage. It now needs very high revs to engage, maybe 3/4 throttle - I'm sure before, the buggy would begin to creep forward if I had the idle set a little high. Wondering whether I've installed the clutch incorrectly. Cheers, Nigel

Many thanks. Yes I had removed the nut. I got in off in the end - just very tight and I was being a bit too gentle. Put a piece of wood over the end and tapped it harder and after a few attempts, it came off okay. Cheers, Nigel

I need to change engines and have got to the point where I need to remove the clutch plate - by this I mean the bit that it attached onto the engine shaft using a tapered collet. Now I've removed plenty of similar with model aeroplane and helicopters and as far as I can tell the only thing holding this plate on this that it is pushed down onto the taper. This is what I have tried so far. Positioned the engine on a vice so that the vice jaws are behind the mounting plate. Then tapping firmly on the end of the shaft with a hammer. I was expecting it just to pop off but it is holding firm. Before I try hitting it harder thought I'd check here to make sure I'm going about it the right way. Thanks for the help. Cheers, Nigel

Never mind - managed to get one from evilbay. Cheers, Nigel

Hi, I'm looking for a good running, easy to handle 21 engine for my son's Hyper 7. It currently has a Mach 28 which is fine but takes a lot of love and care to tune and once done it doesn't stay in tune for long. So would like something that is easy to use and more forgiving that my son can use on his own. I'm not an expert but I'm pretty sure it must be a Hyper\Hobao engine as we have a rotostart which has a backplate for that make of engine (I assume it wouldn't fit on other makes). Not to bothered about clutch, pull-start, exhaust etc. Also not to bothered about age, use as long as it has good compression and runs well and easily. Perhaps you are planning to upgrade your current engine - let me know what you have. Cheers, Nigel

Many thanks. I think you may have helped me solve a long term problem I've been having with my Mach 28 engine. Firstly, the brake was on slightly at low revs which probably accounts for most of the negine stalls I was getting when trying to pull away. Secondly, and most importantly, in playing with the brake arms I noticed that the closing of the throttle was erratic. I had set the throttle stop correctly (1mm) but I noticed that the throttle was often sticking open at around 2-3 mm and closing down to 1mm very slowly - if I applied the brakes it would push the throttle closed quickly (but that's not a good solution). So I adjusted the angle of the throttle rod in the servo horn and also increased the spring tension a little - the throttle barrel now opens and closes swiftly as you would expect. I also adjusted the brake rods so that the braking effect is stronger. Did get to run the car properly at the weekend but did try the engine out in the garden and it seemed to be running much nicer. Cheers, Nigel

Are there any guides that someone can point me at which explain how to set up the brakes and throttle on my son's Hyper 7. Today, I noticed that there was no movement on the brake at all when I pushed the throttle 'backwards'. I also noticed that the brake is on with the throttle in neutral. So I adjusted the throttle trim so that the brake just 'comes off' but the throttle is too high then and the wheels spin and the car creeps forward. Please note that the throttle stop on the engine is correct at 1mm. I looked at the linkages and they are a little complicated. I also notice that one of them moves too far and hits the fuel tank support. So I'm guessing these links need adjusting - just hoping there is a guide which explains it all - otherwise will just figure it out myself. Cheers, Nigel

bump. Still looking. Cheers, Nigel

I'm sure it varies from store to store but the bikes I have seen built by my local Halfords (one was my sons and the other five were friends of my son and duaghter) have been truely horrendous. All they do, in my opinion is straighten the handlebars, put the pedals on and give it a quick ride. The brakes on my son's bike were way out. The head set on the bike of my daughter's friend was grinding away (as if there were bearings missing or no grease) - when her mother reported it she was told, all bikes are like that to begin with, they bed in after a few weeks. Another, the brake lever assembly fell off within hours of taking it home. I wouldn't touch Halfords for bikes with a bargepole, but that is based on the personal opinion of my local - plus I have 3 real bike shops, all selling cheaper than Halfords (for the branded stuff) within 10 minutes drive. Cheers, Nigel

Are the Hobao 21 and 28 Pull-Starts the same? I see that ModelSports sell them as different items but they are the same price and when I look at the exploded diagram for the 28 engine, the backplate and hexagon drive are the same part numbers as for the 21 engine. The pull start itself does have a '28' part number but since it only connects to the backplate and the hexagon drive I can't imagine how it could be any different. Anyone know for sure. Basically, I want to know, if I bought a Hobao 21, could I use my Hobao 28 pull start on it? Cheers, Nigel

No personal experience but I have seen a few and read some reviews. Basically, in the small electric helicopter world, it tends to start off that one main company distributes a product under its own name. If it proves successful, then other distributers start and you start seeing the same helicopters but with different names, different colour schemes and slightly different components. The main components stay the same but you might have different electronics, slightly different bodyshell etc. Essentially, they are all pretty much the same. The main differences is that you will get some companies that really try and shave of the

Fuel - Model Technics Big Bang 20 Sounds like consensus I need to lean of the LSN - I'll certainly give that a go. Cheers, Nigel

Thanks - certainly intend to try that. As I siad I'm starting from a clean sheet and working through the guide. Still on the HSN and could only play with it in the garage today so couldn't give it a good run (not that sort of neighbourhood). I posted because the behaviour just seemed a bit weird to me. How are you getting on with your Mach 28? Must admit that I've had little joy so far and am prepared to buy another engine if necessary. It just bugs me that I should have to do that. Cheers, Nigel

Pretty much agree. Learning to fly a coaxial will certainly teach you essential stick co-ordination, especially as you say, with nose-in. However, I don't think it will prepare that well to flying a conventional heli - anyone coming from a coxial won't have that much advantage over a total newbie when it comes to learning to hover. I don't agree that a Honey Bee needs that much space. It's certainly more twitchy than a Blade but it's smaller and lighter. As for damage, the things that break and the cost are more or less the same - although I agree you are less likely to crash the blade than the Honey Bee. I suggested the collective version of a Honey Bee (or equivalent) simply because they are more fun and I reckon it's slightly easier to fly collective than fixed-pitch. I only got a blade because I liked the idea of something to fly indoors but mostly to try and get my son of his XBox. But he hasn't shown much interest and I soon got board with it. Had it for a year now and I reckon I've only charged the battery 10 times at most. I maintain it's down to what you want to get out of it. Cheers, Nigel

bump

Do you mean the sticky on this forum - How to Tune an Engine. If so, then yes I have read that. I'm generally okay with engines - been flying RC helis and planes for around 20 years but new to cars. If no, then what is it - sounds worth a read. Basically, the LSN is at factory at the moment. I'm following the instructions "get your HSN right before you touch the LSN". I've tried leaving the glow starter on and it still does it. What puzzles me is that it doesn't do it all the time. If it were the LSN then I would expect it to cut all the time - but this isn't the case. If I can coax it pass the cutting then the acceleration is crisp - maybe not perfect but good enough. So how can the LSN be massively out at one point and then pretty close at another without touching any needles in between. It's also not a hot or cold thing. It can get into one of these moods whether its stone cold or nice and toasty. Cheers, Nigel PS Tried a variety of plugs all new - they all start the engine fine and make no real difference to its performance or problems.

I'm still trying in vain to tune the Mach 28 in my son's Hyper 7. Please don't launch into "The Mach 28 is a pig. Doesn't hold a tune" - I've heard it so many times and I'm sure it's true but doesn't help me in the mean time. Anyway, I have changed all the O-Rings, all the fuel tubing, made sure everything is nice and tight and set all needles to factory. Start the engine, deduced the HSN is too rich and have started leaning it off (still some leaning to go). The problem I have mostly with the engine is stalling as soon as throttle is applied - not a splutter but an instant stop. Out of interest I put the hyper on blocks so no load on the wheels and it still sometimes cuts dead. Usually when it's in this mood, if I open up the throttle very gently I can get it to full throttle and then it will throttle fine - instant throttle no cuts. I wondering whether I'm concentrating too much on the engine because when it runs its fine. Could it be anything else causing the sudden cut - clutch for example? Cheers, Nigel

I know it's a lot of money but I can't recommend a good gyro enough. I bought a TRex 450 as a kit and it came with a heading hold gyro. To be honest it was rubbish - yes it would lock but then it would drift and a couple of time it got confused and forced a high speed piro before it locked again (very scary). I replaced it with a Futaba GY240 (wish I spent a tiny bit more on a GY401). But even the GY240 is light years ahead. It just locks the tail period. The downside over the 401 is that it has a much slower servo drive so it piros\turns much slower than the 401. Now these are expensive but worth it. New the 401 is around

The trouble with the coaxial helis are that they are just so stable you can feel quite detached from them. Going into some of the science (apologies if you know this already). When a helicopter's main rotor turns it also has a lesser effect of turning the helicopter - this is why you need the tail rotor. With a coaxial, you have two rotors turning in opposite direction so whatever effect they have on the helicopter body is cancelled out - so you don't need a tail totor. Not having a tail rotor makes flying feel quite different. Additionally, the rotor design of these models is very stable - the equivalent of having lots of dihedral on a fixed wing plane so they more or less hover themselves. A normal heli takes quite some practice just to hover on the spot. This is good in that you get a sense of instant acheivement but the downside is that it makes the control of the helicopter very sluggish. Again very good for the beginner because movement is slow and you can fly around the room very quickly. However, you will soon progress beyond its capabilities and you will find that moving to single rotor heli (either fixed pitch or collective) you will find that flying a coaxial has done very little to prepare the way. So if you just want a toy heli that is easy to fly then I'd say go for a coaxial but if you are looking for something to challenge you with the intention of developing further I would say go for the Honey Bee (or similar - if you can find a collective one, so much the better). The downside to the Honey Bee is that there is no instant gratification and many owners give up at an early stage. I wish you lived closer - you could try my Blade CX2. Cheers, Nigel

For that size, even the most basic servos will work. Try these http://alshobbies.com/shop/lookupstock.php?pc=7314&Desc= I tend to like to use bearings for extra precision http://alshobbies.com/shop/lookupstock.php?pc=5484&Desc= Cheers Nigel

Learning to fly a heli on your own is hard -they are inherently unstable. Actually, the bigger the helicopter the easier (in some respects) it is to fly. I own or have owned the following Century Hummingbird - fixed pitch, very similar to Honey Bee you've linked Blade CX2 - very very stable contra rotating rotor Century Hawk 30 - 30 sized IC heli TT Raptor 50 - 50 sized IC heli Align TRex 450 - a minature raptor in electic form Off them all, my Raptor 50 is the easiest to fly and most stable in the air. Much of this is to do with the size of the disc (gyroscopic effect) and the weight of the heli hanging from the disc (pendulum effect). Going through them, the Blade is extremely stable, once trimmed it will sit pretty much in one place. The downside is this makes controls struggish so you are limited what it can do and will soon outgrow it. Hummingbird - Very small and light. The plus is that they largely bounce of things - but you will still find yourself spending lots on blades, landing gear etc. The downside is that they are very skitty and don't believe any clames about flying them outside. On an absolute still day perhaps, but the slightest of draughts plays havoc with them. Also you will find the fixed pitch limiting and will soon outgrow. TRex - A great heli. Will do practically everything. Is more stable than the hummingbird. The downside is that this is outside only (unless you have a sports hall handy) and to do more than just hovering you need a big garden. Then can also do damage to themselves and other things. They also work out almost as expensive as a 'full-size' IC heli once you start putting decent parts on it to make it fly well. These don't bounce but parts are generally cheaper than their 'full size' cousins. Hawk and Raptor - You really need a club and someone to teach you the basics. Nice and stable and the great thing about helis is that it is a beginners heli or a full-3D model - just the way it is set up. Downside is that when you crash (and you will, a number of times) the cheque book get hit hard. If you need any specific advice just give me a shout. Cheers, Nigel

Do you want to build or almost ready to fly? What simulator do you use and what proficiency? What sort of flying - funfly, scale, sport (bashing), aerobatics? Where will you fly? - Do you have a field or club sorted out. I assume that you know that you can't use car electrics (Rx and Tx) - needs to be 35MHz or the new 2.4GHz stuff. Cheers, Nigel

Last year my son wanted a Nitro Buggy for his birthday. I was all set to buy a new Hyper 7 when we spotted what we thought was a great used deal on here - it was for a Hyper 7 28 with lots of good quality extras. Trouble is, the Mach 28 engine has always been a pig and we have never got it running reliably. I have just stipped it down and replaced all the seals but it doesn't look like it is any better. Anyway, beginning to just accept that the engine is rubbish and we need a replacement. Don't care about size - he's not intrested in organised racing just mucking about (bashing?). So anyone got anything spare since upgrading. Must be reliable enough for a 14 yo teenager to operate without getting frustrated. Forgot to add - Must be pull start Cheers, Nigel