Everything WR8

[sidewaysjim]

I've given up. Reset my needles to factory. I am definitely glad I've bought a flux aswel.

Looking forward to retuning but there isn't really anything less fun when it doesn't work how you want it to.

This has helped me decide that I'll get the nitro ken block shell though, as this car is quite likely to become a shelfer... Lol!

Edited August 4, 2014 by sidewaysjim

[J.A.Son]

Damn! That is the worst feeling. I guess it's better than a broken motor shaft I have had that happen to me twice...

That is why I upgraded to the HD drive cups all around, I'm pretty sure the worn cups caused some massive driveline lash and the motor shaft just couldn't take it.

Do you have any worn cups on you car? Or are you running the HD cups too? (I forget..)

Hmmm, there is a bit of wear on the f&r input shafts, nothing too bad, but enough to cause some lash! Might be time to upgrade these to the HD cups!

I was wondering, was this a coincidence of a result of tighter diffs, hot sticky tyres, high grip surface and some heavy accelerating & braking- I had to check out new diff setup! Saying that there's what looks like evidence of some debris in one of the spur teeth, so prob coincidence- was original pinion at the end of the day.

I'm liking the R7-100-F10 diff setup- nice and pointy yet tail happy when required..

[Mgozzz]

Yeah it's really hard to say what it is from. The first time my shaft broke the pinion was fine but the cups had some pretty deep notches in them. I put the new motor in it when it came in and a few runs later the pinion broke a tooth and the motor shaft broke again.

 

I talked to HPI support about it and they said that it could have just been debris in the mesh, they actually kind of dismissed the drivetrain lash when I suggested it. So it could very well have been a stray rock and the age of the pinion. There isn't a solid way to find out...

 

I haven't had any problems with mine since installing the HD cups (knocking on wood!) but I'm also running a 5mm shafted motor now. I really didn't want to have to worry about it again so I went all out ;-)

 

So some good news! I just picked up the GoPro Hero 3 from my office =8-D I'm going to be trying my hand at making videos this weekend!!!

[Syncro]

I would actually go with silicon diff oil. I use the Team Associated Silicone Differential Fluids. They are made by Lucas Oils and they are awesome.

For starters go with 7k rear/100k center/10k front. They are $5 usd at tower hobbies for the 2oz bottles. They will each probably last you many rebuilds.

Think I'm going to try this diff oil setup on mine.

It seems a little bit quick to swap ends.

Just to check, 7000wt rear- 100000wt (stock?) centre- 10000wt front.

I've never found a good conversion between CPS, CST and WT.

Edited August 6, 2014 by Syncro

[Mgozzz]

Yeah that's what I used. Also I'm pretty sure the associated oil is in cst. So 7k/100k/10k

That's is just a starting point. For me that combo ran really well on high grip Tarmac.

[J.A.Son]

+1

[Syncro]

Yeah that's what I used. Also I'm pretty sure the associated oil is in cst. So 7k/100k/10k

That's is just a starting point. For me that combo ran really well on high grip Tarmac.

Ah right, so 7000cst, 100000cst, and 10000cst. Not Weight.

[Mgozzz]

Indeed.

[Syncro]

I apologize in advance, I'm sure the discussion on oil viscosity has happened many times.

Is CST and CPS the same?

I didn't think it was.

This chart says it is though.

http://www.engineeringtoolbox.com/viscosity-converter-d_413.html

[Mgozzz]

Alright, I finally strapped a GoPro to the WR8... Sorry for the lack of cool music and all that stuff, I haven't the patience for video production so it is just pure driving bliss ;-) BTW the audio cuts in about 1/3 the way into the video so be warned! I don't want anyone pooping their pants.

 

Without further ado, here it is, Mgozzz's WR8 Flux-

 

 

Let me know what you think!

Edited August 7, 2014 by Mgozzz

[Hotshot888]

Nice! Look at those tires ballooning...

Bring back some SRS4 belted tires please HPI...

[Mgozzz]

Right! Funny you mention that, I just picked up 2 sets of the 27R's and 1 set of the D30-40's off of Amazon. They were some old stock from a hobby shop that is finally starting to sell their stuff online. 

 

So my raw unedited video finally finished uploading. If you like tire ballooning and suspension articulation it's a good watch ;-)

 

[J.A.Son]

Cool location Mike! Although the socks let it down! Lmao

Great to see the front end working away and as for the tyre blooning- that's like having a 2 speed, gives you extra top end! Look at top fuel dragsters, lol.

How much of a difference in speed compared to stock motor do you recon?

One final request- some rear ward facing footage would be cool..

[Mgozzz]

Hahaha.... I had just got out of work, changed and thrown on my slippers ;-) I realized afterwards that I probably looked a bit goofy ;-)

 

You have a point there! You know as long as the toe is dialed in the ballooning really isn't all that bad. The car pulls nice and straight regardless of it at this time, previously though, before I had set the front toe I couldn't get on the throttle and keep it straight. It was just uncontrollable... 

 

So speed wise? I really don't think it improved much at all. I upgraded just for reliability really. I wanted to be able to run 3s all the time and not worry about stuff overheating, motor shafts snapping etc. I think it improved the torque more than anything, it will practically spin the tires off the car from a stand still ;-)

 

FWIW all those videos were taken from a storage charged battery, she has a bit more in her ;-)

 

Rear facing video is my next step. Depending on the weather tomorrow I'll be posting some more then.

[J.A.Son]

Weather? GoPro is waterproof, lol!

Iirc, didn't you experiment with a 5mm castle rotor in the Flux can? Wasn't the rotor 1-2mm shorter?

[jamesd]

Ah right, so 7000cst, 100000cst, and 10000cst. Not Weight.

 

 

Indeed.

 

Ah nut's! I thought it was weight and I have just renewed my center diff with 100k wt oil and ordered 70k and 10k weight for the front and rears. Is there much of a difference?

Edited August 7, 2014 by jamesd

[Mgozzz]

I'm not sure what the difference is. What kind of oil did you end up buying?

[Mgozzz]

Weather? GoPro is waterproof, lol!

Iirc, didn't you experiment with a 5mm castle rotor in the Flux can? Wasn't the rotor 1-2mm shorter?

Yeah it is but my esc isn't ;-)

I did try that out. The 3800 shaft actually fit in the can, the issue was that the shaft didn't fully rest in the rear bearing. (It was maybe half way in)

I had driven it a few times like that and it seemed fine.

[Syncro]

Ah nut's! I thought it was weight and I have just renewed my center diff with 100k wt oil and ordered 70k and 10k weight for the front and rears. Is there much of a difference?

Try this.

http://www.offroad-cult.org/Special/cps_wt_umrechnung/cps_wt_convert.php

[jamesd]

I'm not sure what the difference is. What kind of oil did you end up buying?

 

I ended up buying this:

 

http://www.modelsport.co.uk/fastrax-cml-racing-pure-silicone-diff-oil-100-000-wt-/rc-car-products/37512

 

and used it in the centre Diff

 

 

Try this.

http://www.offroad-cult.org/Special/cps_wt_umrechnung/cps_wt_convert.php

 

Thanks thats a handy tool Diff oils are confusing

[Syncro]

I ended up buying this:

http://www.modelsport.co.uk/fastrax-cml-racing-pure-silicone-diff-oil-100-000-wt-/rc-car-products/37512

and used it in the centre Diff

Thanks thats a handy tool Diff oils are

confusing

Having said that, the WR8 seems to list oils in 'wt' so I'd guess you've got the right stuff.

[J.A.Son]

I have a few different brands of silicone diff/shock oil. Associated and Mugen have their viscosity in cst, where as Fastrax have nothing other than the number, which could well be cst as they are not a USA brand?

Doing a very rough comparison by eye, of the speed with which a bubble in each bottle moves they all seem comparable IMO..

I think the WT is used arbitrarily as a generic term, as in the case of the WR8 manual, lol.

[J.A.Son]

And as if to prove the point, using that conversion tool to convert HPI's 100000WT centre diff recommendation you'd need 5,210,635 cst/cps! Try getting that or better still 500000wt equivalent at 35,112,516 cst/cps! Lol

Edited August 7, 2014 by J.A.Son

[Syncro]

I'll be honest, I do find the different methods of measuring oil viscosity rather confusing.

[jamesd]

And as if to prove the point, using that conversion tool to convert HPI's 100000WT centre diff recommendation you'd need 5,210,635 cst/cps! Try getting that or better still 500000wt equivalent at 35,112,516 cst/cps! Lol

 

Hahahaha I got that result as well and thought i must be doing something wrong! So is 100k Wt fine for the centere diff, and I should try 7k cst on the front and 10k cst on the rear not 7k, 10k Wt?