InitialD

Ok, I I'm gonna start a new Serpent Impulse thread since it doesn't help that after several weeks, the non-HPI forums looks like they are gone for good...

Mytsn is currently down indefinitely because of the provider change also does not help us...

So post away...

fuse01

yes finally, i feel so left out.

i was wondering if anyone of you change to a 3 piece clutch instead of the 2 piece shoe? i have the centax but is rather useless in our tiny tracks and tall gearing of 15 /18 i'm currently on 14/16 and 50/47

the 2 piece shoe failed me a few time when the spring broke and i ran like a turtle. can anyone advise me if there is a replace ment for 3 piece clutch like the mugen mtx2? or is there any way to make it work better?

i would also like to know what will happen if i toe in the rear 2 deg and also toe in the front 2 deg...? ??

currently running 3deg toe in rear and 3 deg toe out front.

I need tons of steering .. please assist.

InitialD

mytsn is down and so is HPI forums. I think someone posted some info there on the non-HPI forums.

Believe me or not but I have not run the normal clutch shoe. All this while, I run the Centax onmy Impulse.

I believe there is a part number for the 3 piece clutch shoe. Will get it for you once mytsn or HPI forums are up (if ever). Personally, I would think that the 3 piece and the 2 piece clutch shoe works the same. Logic says that if the spring will break in a 2 piece clutch shoe, it will also break in a 3 piece clutch shoe.

I think the only thing different with the 2 piece versus the 3 piece cltuch shoe is that the latter grabs better.

I still say that put the Centax in your car if you want reliability. What you can do to your Centax is to tighten the spring so that the car will launch at a higher engine RPM. That will pull your car harder from the standstill.

Else, do like what Serpent is suggesting on the 705 FAQ. Change the drivetrain ratio on your Impulse.

Change the 18T to a 17T side belt pulley (new part number). For this, you need to have the 9619 MK2 adapter. Next, change the 23T brake pulley to 22T like what you have on the Impact. This also needs a 9614 Aluminum brake pulley adapter. Also, change the 46T diff pulley to 47T like on the Impact. That will effectively give you a 14T pinion on the Centax.

All the other pats are available except for the new 17T side belt pulley part number. You'll have to wait at least till the 705 comes out.

Else, get a 13T/16T fixed pinion Excel clutchbell

Question on car setup, in order to get more steering is to set the front to have more grip. You can set the front gear diff loose or better still drive a one way front diff. You can set brake to very slightly so that the car will not swap ends in the rear. I have tried this successfully on a tight track. It needs some practising. By the time you're done, you'll notice that you will be able to take corners shaper than the others.

Other ways to increase front traction is to use softer front tires, softer front springs, increase rear droop, limit front droop (in order to shift the weight to the front of the car) lower ride height in the front than the rear etc. Using 3 degree toe out in the front will increase the turn in response into a corner.

Putting 3 degree toe in increases rear stability but cuts out straight line speed. Well, you can try 2 degree toe in and see if you can still get the same amount of rear stability.

PUNISHER

iTrader: (2)

Try useing the Mugen clutch springs there are stronger then the Serpent ones. So that way you can still use your Serpent 2 shoe clutch.


I use to also break the serpent springs untill i tryed the mugen ones.......havent broke one since!!

InitialD

Good tip punisher I guess it's just you and me here Where have all of the rest of the HPI forum went?

Pit-racer

iTrader: (4)

Finally a good serpent forum is back! I'm waiting for a new 705 also, still running an O.G. impulse.

InitialD

It can be good when we get the old guys back from HPI here... Seems the forum here provides for a more stable existance.

We had quite a few Serpent threads missing after the last HPI forum shutdown (before this last one). Versions 1 till 6 just went kapuuufff

Before this last indefinite shutdown, we were at version 8.

fuse01

thanks for the tips

i shall give centax a miss as my car is extremely heavy..with mod adj rear sway bar, FPS rear diff....and street spec top plastic deck.
the carbon one broke and the plastic one is a better choice as i can mount the receiver on the right side instead of near those hot pipe and running belt.


i'm currently using light weight hub bearings with plastic spacers from team magic and so far it works well.

mugen spring? ok pal.. i shall try it on the coming race.

thanks

great to see the snaks drivers are still up and running.

toolmon

Hi guys,

I run 24mm rubber tires on my Impulse. I was just wondering what brand/type rims fit the best. I'm currently using Yokomo Precision dish wheels, but the wheel's inside diameter is still a little too small. I tried the RD Logics ones, but they break too easy since they're made out of polycarbonate. I prefer ABS, 'cause nylon bends and polycarbonate is too brittle.

I already sanded the rear uprights and steering blocks where it hits the inside of the wheels, but I don't want to take too much off. I'm afraid it will weaken them.

Thanks

InitialD

fuse01, if you like the old plastic radio plate, you'll love even more the one from Wolfpack. It's stiff (maybe slightly heavier) and the receiver is in between the throttle servo and the tank. You can use the same conventional flat pack type of assembled batteries that you can use with the plastic to radio plate. On the Wolfpack radio plate, the batteries can be installed at the back in between the tank and the radio plate support.

I also don't quite like the graphite upper deck on the PRO as for one thing, it breaks, and the other thing is you are only limited to the measly 700 mAh AAA batteries.

I find that when using digital servos for both my steering and throttle / brake, I could get reasonably long run times (approx 1 to 1.5 hours) but once I added the external fail safe device, my run times went down. I think the fail safe kicks in conservatively when the voltage dips down a little.

InitialD

I use Ho Bao rims. I think it's the same as the Ofnas you get over there. They are hard and their hex nut grooves are deep.

InitialD

Ummm, how much did you get them in SG? Where?

Is this the one (151019A) as attached in the pic below?

How much lighter did it make your Impulse? Any difference in handling? It is suppose to reduce unsprung weight in order that your shocks can work and respond better.

Morpheus2be

Well, I've gone thru my 2nd front belt in a month! I wanna get the front aluminium pulley mounts. I remember Rookie Solara putting in belt tensioners, was that for the front belts? If it is, where can I find it? What parts do I need to make the mod?

toolmon

Thanks for the info InitialD. I’ll give the Ofna rims a try.

InitialD

I've also read and was to a certain extent convinced that on some cars like the 1/8 scale MRX3, aluminum pulleys lengthens the life of the belt...

However, my very own experience tells me otherwise. I have a custom made 16T aluminum pulley that I use and I seem to break the front 5mm belt more often. It just snaps. Maybe it's also related to the very high punch I now get with the newly acquired 13T/16T Excel Centax clutchbell. Since putting back the stock plastic pulley, I've gotten more life out of them... Go figure.

Rookie Solara used a universal front tensioner from Wolfpack. In fact, Wolfpack does make a specific aluminum mid bearing block which includes a front belt tensioner. The mid bearing block tightens the front belt via a eccentric cam which when you rotate it, at the same time it "moves" further away backwards and hence tightens the front belt. The thing is while doing this, the side belt gets looser. Then again, you can use the already provided side belt tensioner. I think only Wolfpack has this kind of front belt tensioner for the Impulse. Not cheap.

I did use my own custom made front belt tensioner. I took it out because it was "eating" the 5 mm nelt I was using. With the "older" 4 mm front belt, it was OK. I think it's because of the very limited space available. I used some belt tensioner from Ho Bao and mad some modifications to mount the tensioner from the top of the radio plate. Yes, I drilled a hole from the top of the radio plate to get access to the front belt.

Anyway, I'm waiting for some modifications to the front transmission to come. It uses the same pulleys and pulley adapters as the Vector with an Impact middle shaft. BTW, you can also use Impact pulleys but you need to get the aluminum pulley adapters for the Impact with the Impact middle shaft.

It seems that this eleviates the front belt / pulley problem. The pins inside the standard nylon pulley-adaptors will develop play after some time of racing and may cause the belt to break. Serpent sells this part as 801350.