I'd change the tires first. Then work on the weight.

 

I would replace the chassis with a 3d printed one compatible with Slot.it parts.A list of chassis and suppliers in forums->1/32 scale cars

 

VonkeyVong, what you've done so far is a good first step. Personally I think that 10 grammes of weight may be too much for a Fly 908, but if you have an accurate means of timing your car, then experimentation is the key. Change one thing at a time, see if it makes the car faster, slower or the same, see how it affects how easy and consistent it is to drive, and then repeat with another minor change. Eventually you'll settle on the best set-up for you, you'll have learned a thing or two, and you'll have saved yourself the cost of probably unnecessary changes of tyres and chassis.

 

For weight: measure the distance from the guide post to the rear axle. Then take 75% of that distance and mark the spot. Suspend the car from that point and see which way it tips. If it tips forward, add weight behind the suspense point until the car is balanced. If it tips to the rear, add weight in front of the suspense point until the car is balanced. What you've done so far is good as far as tires, axles and braids are concerned. Try the car after it's been balanced using the "suspend at 75%" method and see if your lap times improve. This is a method that was used by one of the top racers that I've known, and his cars always ran competitively in a "box-stock" racing program.

That method improves handling while avoiding any additional expense, though replacing stock chassis with something like a 3D printed Slot-It compatible chassis will definitely improve handling as well.

 

On the other hand, your 908 may be like mine was.
After some time on the shelf it developed literal pools of oil under each of the wheels. This had leached from the tyres. These were, without exaggeration, now as hard as plastic, with no rubbery softness or grip at all. I put the car on the track, pulled the throttle and the car remained stationary with the wheels spinning fruitlessly. I tried to peel the tyres off but they had become so brittle that they simply cracked and dropped off.
As for other tuning, I replaced the floppy front plastic half axles with steel ones. These used to be made by Avant Slot but are, unless someone knows better, not available nowadays.
Michael

 

Yes, that nightmare happened to everyone who purchased early Fly cars. It will probably happen to yours too, Matt and if it does just buy some NSR 5218 tyres and it will go better than ever.

Andy

 

QUOTE (stumbley @ 28 Jan 2017, 01:52) <{POST_SNAPBACK}>For weight: measure the distance from the guide post to the rear axle. Then take 75% of that distance and mark the spot.
Hi Stumbley,

Am I right in assuming the 75% spot is measured from the guide post towards the rear?

Regards, Jan.

 

Yes, Jan, that is correct. 75% of the distance from the guide post to the rear axle.

 

... so on top of the motor in most cars, then?

There's nothing wrong with the 908 in standard trim - it's one of Fly's best efforts. When running non-mag I tape a coin in front of the motor if needed, which is just to keep the guide in on bumpy tracks. Yes, you can change the tyres. But it's not mandatory. If you're running in open or club competition there are many better tools for the job so enjoy it for what it is and don't spend another £50 on parts trying to keep up with them?

 

I have glued the motor pod/axle carrier to the rest of the chassis on a couple of Fly cars, then left out the rear screw.
Seemed to help.
The solid front axle is better than upgrading the single stub axles in my opinion.
Depending on your track surface NSR or some urethanes would help....oh and trued hubs can also add to the smooth running.

 

Thanks for all the great replies.

I want to keep it as simple as possible. The club I want to use it at doesnt go in for letting you change much either so a tyre swap (have to be rubber tyres will probably be the only other thing I do to it on top of sorting out the front axle. The tyres on it are the original tyres and are actually very sticky but do tend to lose the grip quickly picking up invisible dust.

I will give the weight balancing method a go and see how it gets on.

I actually find it a fun car to use on my short home circuit, so much so that I am going to buy a SRC Porsche 907K and 907L to compete against it.

Matt.

 

So, using the 75% technique I have balanced the car with two 5g weights, one in either side of the shell at the tail. It still gees well but has a bit of a skip under acceleration which I need to cure and is possibly a bit light at the nose.

I have just ordered the SRC 907L and 907K from Top Slots 'n' Trains at £25 each along with some NSR5218 tyres.

Matt.

 

QUOTE (VonkeyVong @ 30 Jan 2017, 05:35) <{POST_SNAPBACK}>So, using the 75% technique I have balanced the car with two 5g weights, one in either side of the shell at the tail. It still gees well but has a bit of a skip under acceleration which I need to cure and is possibly a bit light at the nose.

I have just ordered the SRC 907L and 907K from Top Slots 'n' Trains at £25 each along with some NSR5218 tyres.

Matt.
"two 5g weights, one in either side of the shell at the tail."
Doesn't sound too good at all, if it's behind the rear axle let alone on the body. Once you get your NSR 5218 tyres glued and trued then address the weight issue. You shouldn't need much at all.

 

I agree with Wobble...not on the body and not behind the axle.

Keep the body screws loose and let the body float a little...that is why I suggested gluing the two chassis pieces into one.

I hope you also balanced the car after fitting the solid front axle.

Enough lectures now...go try some things.

ps I also edited a couple of previous comments after a report from a member.

 

QUOTE (munter @ 29 Jan 2017, 23:14) <{POST_SNAPBACK}>
ps I also edited a couple of previous comments after a report from a member.

Munter,

As it was my post (post #4) that was butchered ("edited" is too grand a description for your work), and the butchered bit was in no way rude, offensive or anything else that would be considered inappropriate by anyone other than a thin skinned fool or idiotic moderator, please remove my entire post. Left as it is it doesn't express what I wanted it to express and I object to it being rewritten, particularly as you lack the decency to inform me that my post has been butchered.

I despair at what's happening to SlotForum. The standard of some of the moderation is pathetic. We have a member who doesn't like something but doesn't have the guts to say so publicly, so he runs to the moderator whining. Mate, whoever you are, you're weak. My guess is that it's Alexis in Greece, as his was a post that I commented upon and he viewed my profile today. Get a life mate.

Clearly this post will be removed by a moderator too, but until it is, below is a repeat of what I said in my original post.

"Oh dear oh dear oh dear oh dear. "Change the tyres", "Change the chassis", all we need now is someone telling you to change the entire car. It seems there are some SlotForum contributors for whom wholesale replacement of most of the car is the only method of tuning they know.

VonkeyVong, what you've done so far is a good first step. Personally I think that 10 grammes of weight may be too much for a Fly 908, but if you have an accurate means of timing your car, then experimentation is the key. Change one thing at a time, see if it makes the car faster, slower or the same, see how it affects how easy and consistent it is to drive, and then repeat with another minor change. Eventually you'll settle on the best set-up for you, you'll have learned a thing or two, and you'll have saved yourself the cost of probably unnecessary changes of tyres and chassis. "

 

Thanks Dopamine

I enjoy a bit of a verbal spar and even though there are some insults thrown my way in your latest post there is some merit to your argument.

There is no way I will touch your post now you have spoken about it. Let others read your words.

Now back to tuning the 908...
I found truing the front tires an added advantage.

 

Looks like I have a lot to learn. I will give it a go moving the weight around I will also try reducing it and see how I get on. I must say that I think I preferred it with the weight a little further forward. I am running it on the club track tomorrow evening so I will experiment some more then.

My cars are basically here for fun. I like the idea of improving a car with very little modification and trying to work with what you have in front of you.

Matt.

 

I remember getting my first Fly Classic, a Porche 908/3. I liked the fins.

Once I had got the tires(all four)trued the car became a different animal.
Other changes I made were: solid front axle, loose body, glued the two chassis segments together using JB weld.

I run on wood.

 

All tuning depends on what track surface you are running on and what modifications are allowed within the rules at that club

Had a email from Colin to say you are coming for a visit tomorrow night

obviously you'll bring it along to try it out, please also bring a note pad and pen (infomation overload

)

Oxford havent run these in a heat race for a good few years. Due to Fly spending more on the body than the chassis, we ran these beautiful classic's with the magnets retained. They can run very well on both plastic and wood tracks without the magnet once the have been fettled with. You can do some basic tuning which will cost you some time and patience to £100 plus, depends on what you want to achieve with the car

Looking forward to chatting tomorrow

John

 

Hello John,

Yes looking forward to it. I will bring the 908 and see what you think. I like it for what it is, its not particularly fast and it spends a lot of time sliding around corners but it is fun.

I have about 25 cars at present, and now I have started to try some without magnets I am actually preferring it. I will bring a few along and see how I get on. I will make a list of the rest to see what can fit in with the classes you run.

See you tomorrow,

Matt.

 

 

One more hint about tuning Flys,rules allowing,motor run-in.It can give you up to 15% rpm increase and up to 20% torque increase .If interested PM me for details.

I have developed a fluid for improving Fly tires,tested on Ninco track they are almost as good as NSR, if interested I could send you a bottle free