Fly Porsche 908 kit, Upgrade parts Options

[craigk1]

Hello,

I don't often post here as by the time I have read through older posts my questions have usually been answered.

I have got myself a fly porsche 908 kit and want to upgrade the rear axle, wheels and sidewinder gear. I have been looking at some NSR axle kits - although open to other brands too - but I am not entirely sure which kit is best for this model.

Kit image

For Fly models there seems to be a choice of three kits, standard diameter air system, large diameter and then a kit (front and rear) for fly classics.

Any help would be greatly appreciated.

Thanks.

[BEEJAY7]

Craig

If you look on my website you'll find an article on upgrading the Fly Classic range, listing the my selection of the parts you can use.

Regards

Alan

[craigk1]

Cheers Alan,

I have now book marked your web page - there are some good items on there.

[AllanI]

Why not do the basics on the existing rear end components. Trim the motor shaft both ends, true the tyres and shim the axle. See how the car goes and if you like it leave it, if not spend the money.

Allan

[Petr L]

Hi, I used for P 908 slot.It components:

36 tooth 19mm SIGS 02
steel axle SIPA 01
Bronze bushings SIPA 02
Pick-up SICH 07

Original rear wheels I glued on Slot.It axle.

[Newimaging]

New to the hobby guys, so I have some of the basic questions. I want to change the whole rear of the Fly Porsche 908 to the Slot.it axel as Alan recommends, but am wondering about the Wheels. We use Supertires on our tracks, how do I know what Supertire fits the BWA Wheels, or is there an easy way to use Slot.it wheels instead and which once would you recommend size wise. And then again, how do I know which Supertire fits those since they are listed by car, not by rims.
Thanks for any input.

Christian

[Moby Dick]

I suggest using Slot car corner CB design wheels with supertires.
You could either go with black anodized 5 spoke, which would be a close match for the originals.
Or go with the insert style wheels they offer and make inserts out of the old wheels.
They have a new tire with a pre rounded shoulder which fit either previously metnioned wheels in 15x11 size



http://www.slotcarcorner.com/images/products/559.jpg



Another trick I do with my fly classics to gain more clearance under the spur gear is to swap the stock 6.5mm pinon with a slotingplus or NSR 7.5mm pinion.
Then you can use an 18mm slotit spur gear and gain an additional .5mm ground clearance and use slightly smaller rear tires.

[DE38]

And then again, how do I know which Supertire fits those since they are listed by car, not by rims

There is a wheel and tire selector on the Slot Car Corner site that will let you select either way, by car or by rim.


For the CB Design, 15x11 5 spoke wheels, Supertire 1007 which fits the stock plastic Fly classic wheels fit the 5 spoke wheels, they also fit the BWA 32005 and with a little persuasion will also work on the 32006 wheels. The stock front tires fit the 15x8 wheels very nicely also. Here are a couple 908s, the Martini car is the kit car mentioned, both using CB wheels and NSR gearing and other assorted mods and tuning.

DE38

[stoner]

why do you want to change a new! perfectly good axle, bearings and gear, for another set. the wheels i can just about understand if your new ones are out of round. but what do you hope to achieve by spending a good deal of money on new parts. its not having a pop at you because loads of people do it. i,m just curious as to why, without trying what youve got. john

[Crusader]

Hi All,

In reply to Stoners comment I would for the most part agree why change numerous parts if you were just using the cars on home tracks, I've got a number of Fly cars, the ones I do use I've replaced the front stub axles for a Slot-it axle but kept the original wheels, as to the rears, well if you're using the cars for Club racing then you'll want to change gear ratio's which means
a new axle and so on, on one of my Fly Porsche's I've kept the back axle gear and wheels which I've glued on, but I've replaced
the plastic bushes with Slot-it one's, they are initally tight due I think to the anodised Fly axle but they do get rid of the axle slop.

I've fitted NSR Classic tyres for Fly fitment as the Fly rims won't accept most other tyres without mods.

Robert.

[DE38]

I do club race on 130ft custom 4 lane wood Ogilvie built track , its a very fast flowing track and you absolutely need to change gearing for this track. I absolutely agree for home racing there is no reason to change out the rear or even the wheels if they are prepped the right way.

DE38

[stoner]

slot it axles arn,t anodised unless there made of alluminium and youl,l find that the top club racers use nsr 2.37 axles in the 2.38 bushes for the free running of this combo. if youv,e glued the bushes in and the axle is tight. take the backend off and run a 3/32 reamer through both the bushes. this should clear up any tightness and binding issues because it sounds as tho the bearings are misaligned. i questioned the term [upgrade parts] i can see the benefit for club racing but even then changing a motor pinion will get you in the ballparkand they do a lot of pinions with less or more teeth in the same od as the original. unless your chasing one thousand of a second 1 or 2 teeth difference on the axle gear isn,t going to make much difference, its all a compromise as in 1-1 size racing. i think 2 teeth on the back=1tooth on the motor. john

[Crusader]

In reply to Stoner's comments I didn't say that Slot-it axles are anodised (they're polished), I said I believed that Fly axles and
for that matter (Scalextric axles) are, re the black coating, the Slot-it bushes were tight on the axles before putting in the car, I
haven't looked up the chart giving axle diameter's but COULD the Fly and Scalex be 2.39mm, after running in, the bearing surfaces were polished metal.

I didn't have my first NSR car until July 11', my 2nd in Nov 11', it was then I realised running NSR 2.37 axles was better in one particular case, I'd got some 3/32 MB Slot Ball-raced bearings and they were a devil to fit, I resorted after oiling to tapping them
onto the axle, I realise now that after using NSR 2.37 axles they're perfect, you learn all the time.

Robert.

[DE38]

i can see the benefit for club racing but even then changing a motor pinion will get you in the ballparkand they do a lot of pinions with less or more teeth in the same od as the original. unless your chasing one thousand of a second 1 or 2 teeth difference on the axle gear isn,t going to make much difference, its all a compromise as in 1-1 size racing. i think 2 teeth on the back=1tooth on the motor. john

Just changing the pinion does not get me in the ballpark, 13/34 is ratio that needs to be run on my track, if I were racing against some who just changed the pinion I d be lapping them every 5 laps, Ive run against cars that were geared 12/34 on my track and that doesnt do the job either, so yea we are club racing and trying to wring speed out of these cars, but we also run alot of stock classes too but in the Fly classic series we run it is a heavily modified class. We are allowed to change all running gear and clearance the chassis for body float but we have to use the stock motor. There have been many races that after 4 3min heats we were within inches of one another at the end .
So yea in the Fly class we are looking to shave 1000ths off our times, its a very competitive class

DE38

[stoner]

is 34 teeth the gear that comes with the standard model you run. if so why dont the guys that run 12-34 just change the pinion to 13 teeth, same as yours. john