Geetoo

iTrader: (1)

HPI is slowly being called HB....change of name?? I wonder why?

Dongskie

iTrader: (44)

Pro4 is still an updated car that is very reliable. Many whom I know stil prefer shaft since it works better on stock races.

pwracing

Hi guys,

I finished building my Pro 4 ready for this weekends nationals and as i gave it a little run to check everything was ok but there was a clicking coming from the rear input shaft. I've changed everything, input shafts, bearings, gears, shims, spurs, pins even gearbox cases but this clicking just won't go away. Please someone I need help!!

Regards
Paul

junbantay

Look Guys...as long as the HPI company see's that the Pro4 Items are moving off thier Storage houses... they will continue manufacturing it and its Parts... so if you have Friends who want to start having R/C as a hobby... Have them buy a Pro4 Kit... No favors between Cyclone or Pro4 but just to keep the Pro4 in the production line. Cause Cyclone is tipping the balance between rumours of what HPI might maintain in the production line.

Pro4 hasn't lost its Glory between the Cyclone.... Belt or Shaft it doesnt matter, both have dissadvantages. its more of How you Drive to give yourself an advantage.... usually some would say Cyclone is better but just because its a New Kit and Belt Driven that it makes Shafts an obsolete thing. I still Drive a Pro4 and mind you I still kick Asssssss on the tracks... I dont Kick just "1" ass... but "Asses"...

Like me, I prefer Spool now than the 1way. I could release the throttle later than the oneways... and Dive-in in Corners, but I dont have the Initial turn compared to 1ways... so its more of Compensation than what you think is the disavantage of Pro4 from a Cyclone. Let alone in general between Shaft and Belt type Cars.

from my point of View... Its more of how you feel your Car and your Driving skills that makes a Bigger Factor... not just the type of Car you Have.

So I Believe Pro4 can still take the Podium.

Also try different internal Settups.... like 1way/Diff, Diff/Diff or Spool/Diff. see how your handling is with these different settups.

I tried it all..... I like the Diff/Diff for practice sessions.... and Spool/Diff
for Race Proper.

wagonman72

I have been driving my Pro4 Hara with a spool lately, my Cyclone Hara is built as soon as I have them both at the track I will be able to give you some kind of impression.

MikeR

iTrader: (15)

You know what's interesting? I went to RCX last week and unless it was covered by bodies I didn't see the Pro4 at the HPI/HB booth They had 3 cyclones in the booth prominently displayed including the new sport version.

junbantay

It's obvious that HPI will be showcasing the Latest models they have in the RCX. the 3 Cyclones you saw might be the Original the Hara and the Suri Editions... plus the new Chassis for Beginners.. the baththub type Cyclone... if Im not mistakin' or something, but its a bathub Kit alright.
hehehe cheaper, and Cute.

With the Pro4.... it has made its Name and don't need to prove its worth to every R/C Enthusiast.

floodo1

its not just shaft vs belt.
the cyclone has lower CofG. look at how tall the bulkheads are on the pro4, also look at how high the shaft and finally the upper deck is. the uppdeck is up at old school 415 height.

furthermore cyclone has single center arm steering, for WAAAY different ackerman. (a setup that tamiya is modifying to work on their system (with the front belt at the center of the car, and not offset like cyclone))

the chassis difference can be seen in the setups, look at the low front "toe" blocks used on cyclone, and always the impression of "the cyclone turns so much".

its ALL in the chassis since they share the same suspensions.



but still, by virtue of using the same suspension the pro4 remains a good car, esp in lower powered classes.

AngryAsian

iTrader: (4)

I haven't run my Pro4 for a while... took it out for a quick spin tonight. (thankfully i has baby smooth concrete right outside my house. Big public museum. THink square 50m X 50m with a straight 150m long leading into it!)

Wow.. i forgot just how fast and resonsive the pro4 was. The old schumacher was fast but it was like a big comfy armchair. Easy... definately fast for sure.. but somehow.. i dunno...

Then comes the Pro4 again.. tickle the throttle and it's off.. Wow.
I suppose that's why i've kept it around. It's always good for a grin..

AngryAsian

iTrader: (4)

That said, if i was more heavily into racing i'd get the cyclone...
Belt cars are just easier to drive. Easy to drive = more consistent results..
I notice that i'm MUCH more nervous driving the Pro4 than when i'm driving a belt...You can pretty much squeeze the throttle as quick as you like with the belt. If you get sloppy it babies you and lets you get away with it.

The shaft is so direct that it's more fidgety on and off power...

With a mod motor, you've got so much power anyway that any loss is marginal. I've never raced stock so i can't comment but i'd imagine that the directness would be an advantage. Cars with lower power (after driving mod) just seem so dead. In that case i'd grab the Pro4 without a doubt.

AngryAsian

iTrader: (4)

Hey guys - i have a problem...

My centre shaft is straight, true as an arrow. I've upgraded to the alu centre drive cups which are very much true-er than the old graphite ones. I've "shimmed" the centre drive shaft with small foam dots to stop it from moving back and forth...

BUT!! with the revs that the GTB is pulling, the shaft vibrates and resonates. In fact, if i leave the car off the ground, it finds a nice frequency where everything goes smooth.

With some load, the shaft vibrates and resonates so much it's HITTING the centre post and scratching itself.!!!

what do i DO??!?!?!?

dodgeguy

iTrader: (208)

Get a belt car.

That sounds like a lot of movement. The shaft itself may be week.

Also normal with dealing of drivline vibrations. Under a load they are worse. (torque sensitive) When the vibration smooths out you are out of the point of resonance. You have something else that you are matching the frequncy causing this. Look at you other rotating parts for bent or out of balance. same speed as the shaft. Or a 2nd order vibration from the dog bones.

hobbipro

iTrader: (23)

I had the same vibration problem with a brand new aftemarket shaft (tobee craft). I have the Sphere in mine with a 3 star (9T), and when I would gun the throttle the shaft would just vibrate all to heck. I stuck a stock hpi one back in it and problem was solved right away. I'm using stock cups with stock spacing, vibration is minimal. I now keep a few spare shafts on hand since the shafts take alot of abuse with mods.

AngryAsian

iTrader: (4)

Hmmmm.. might give it another go with another spare shaft i have. Surely it can;'t have bent already. it only has one track day on it!!..

Or maybe i'll try it without the foam.. let it move back and forth a bit more..

It's never happened so badly before. Not even with the original shaft which was twisted AND bent!!.. the irony!

BrainTeased

iTrader: (4)

it could be the foam like you suggest not allowing the shaft to stay central due to the tight fit between the outdrives.

either that or it could be either of the front or rear input shaft bearings ceasing up causing the input shaft to not be truely central while at rotation under load. and check the screws that holds down the diff casing where it clamps down the input shaft and drive cups.

would be interesting to find out what caused the problem