Toad16v's XV01 build

[Pylon80 2618]

22 hours ago, Toad16v said:

Set about the shell over the last few days. I've not got the patience, skill or dexterity to do a decent box art job on it, so I didn't. I used some ps23 gunmetal in the past and loved the colour, so went with that. Most of my other cars are blue or shades of so I thought it would be a good change.

The supplied window masks were handy, and I used the light cluster masks while I was at it, incase I get really bored and want to fit lights. Dashing in and out between showers, using the heater fan and a can and a bit of paint got the shell done, I didn't back this one with any other colours as I didn't think it was necessary. I had some of the correct black ts paint for the roof vent and mirrors in my box of paint cans, so they had a few coats too.

Not wanting to use all of the stickers, and wishing to retain the will to live, I went through the manual, marked the stickers I did want to apply and numbered them sequentially. I made a few little mistakes such as fitting a headlight sticker incorrectly and out of sequence, but I'm sure after it's been rammed into a few inanimate objects I won't notice. 

After probably 3 hours in total of stickering, I finally achieved my desired result. Basically a road going car.

Once complete I took it out for a good blat around the street. Still super pleased with it, really pleasurable drive and also quite easy. The tt01 is a great, fun, probably quicker with its current gearing car, but this is awesome, predictable and just lovely.

 

 

 

 

 

Looking good. Now let's cut these body posts!

[Toad16v 282]

2 hours ago, Pylon80 said:

Looking good. Now let's cut these body posts!

Haha, yeah, might trim them down a bit. The other shells use holes lower than this one, so it won't hurt to nip a few holes off each.

[Toad16v 282]

Our lovely postman arrived yesterday lunchtime with my parcel from rcmart containing carbon reinforced parts for the spur gear retainer, front universals and a spring set. Stripped the front end and replaced the spur retainer first. Unsurprising that it had stripped when it appears only a couple of threads were in the rear part. A slightly longer screw would have been a definite improvement. The new parts feel nice and solid, so I'm happy. Adjusted the motor meshing while the cover was off. Was probably slightly too tight before.

Built the universals with a tiny smear of AW grease on the pivots, undid the front hubs, removed the stop screws and fitted the universals without much hassle. They seem to have slightly more play in them than the original axles, so I've fitted 0.2mm shims either side to reduce slop. Reset the end points on the controller and had a quick test drive only to discover that the servo screw was loose again, have removed it, put locktite on and hopefully it'll hold firm. There does seem to be a bit of vibration from one wheel, I guess it's just not balanced correctly, I'll try rotating it on the hex and see if it gets better when I reset the end points now the servo saver is tight again.

Was difficult to tell if the car drove very differently last night. It had been raining and it was difficult to keep the car under control on the wet asphalt.

[Toad16v 282]

It's a horrible, wet day here in Hampshire so I set about putting the aluminium pulleys on for the belt. I had planned to leave it till I needed to do some other maintenance, but there really isn't anything better to do today.

Took the front left wheel off, detached the shock at the top, removed the rear wheels, wheel wells, belt cover and took the gearbox mounting screws out so it could lift up a bit to help get the belt off. The circlips weren't too bad to get off with pointy tweezers and rotating them to the flat on the shaft, then it was a case of pulling off the plastic pulley and spacer, fitting the aluminium spacers, pin and pulley and putting the circlip back on. Luckily these are a lot easier than either the damper shaft circlips or the circlips on the clutch of some of my chainsaws and they didn't ping off into another dimension.

Everything went back on nicely in reverse and now I'm bored waiting for the rain to stop again.

 

 

 

 

 

 

 

 

[Toad16v 282]

Ran it again tonight, having a go at the postal racing circuit. Noticed the tracking was off, and in trying to pin it down noticed that it wasn't consistent, very much like my Dark Impact. After a bit more fiddling I discovered that the stock servo saver wouldn't centre and would stick either side of centre depending on the most recent steering input. 

I had already bought the high torque servo saver, but hadn't fitted it as my servo is only an 8kg unit and I didn't want to put stress on it, however with this wandering issue I decided it would be a good replacement. Because of the lack of strength in the servo I've only used the two inner springs, and left the large outer spring off. Hopefully this won't mean I damage the servo in any impacts but it performs correctly unlike the stock unit. 

I used a flourine coated ball when putting it together. Super slippy and smooth!

[Toad16v 282]

Sorted the tracking, then set the endpoints. Had to shave the corner of the high torque servo saver off to avoid hitting the chassis, I understand the aluminium horn now! 

I think the end points could be set a bit further over, but I get an occasional u pleasant rattle at full lock when accelerating from low speeds while the car is sat on the stand. It doesn't occur while at full lock at mid to full throttle, so I think it's a harmonic type vibration from the tyres rather than the universal joints but I've decided that conservative end points are better than some damage down the line.

Once everything was reset I took it out for another hoon in the street, definitely feels a bit better, I think the slight wander from the servo saver had a more significant effect than I realised. Looking forward to putting more hours on the car now.

 

 

[Toad16v 282]

Fitted the medium springs from the tuned spring set to the front, to try to stiffen it up a bit. I've found it dives and rolls a fair bit on tarmac, and the body catches every so often on the rougher patches. I'm not sure it's that much better than it was, but I think the rear end slides round a bit more easily on corners.

The outer edge of the tyres are wearing, and I suspect a tiny bit more camber might help with their wear and a little bit more grip.

Had a really solid 5 minute session on the postal racing circuit today, driving smoothly and consistently. Then I couldn't repeat that level of driving. Hopefully it'll become more natural as I drive it more and more.

Having experienced the motor getting hot, I trimmed the front bumper a bit to try to get more airflow over the motor. Maybe it'll help...

[Pylon80 2618]

On 8/22/2021 at 12:31 PM, Toad16v said:

Having experienced the motor getting hot, I trimmed the front bumper a bit to try to get more airflow over the motor. Maybe it'll help...

I think removing a tooth or 2 from on the pinion will cool your motor more than anything else. Postal is done on such tiny little tracks that the gearing can be set very low, even by rally chassis' standards.

[Toad16v 282]

On 8/26/2021 at 12:59 AM, Pylon80 said:

I think removing a tooth or 2 from on the pinion will cool your motor more than anything else. Postal is done on such tiny little tracks that the gearing can be set very low, even by rally chassis' standards.

Yeah, I think you are right. I'm on the kit pinion, so can only drop 1 tooth, and I'm not certain the motor will actually move enough. Will experiment at some point though.

[Toad16v 282]

Have been running the car regularly over the last few weeks, and trying to find ways of eeking out gains, or at least what I perceive to be gains or improvements. 

I had a set of aluminium 4mm spacers delivered to replace the nn4 units, along with some of the tamiya 4mm spacers to fine tune the play in the gearbox shafts. When I come to strip gearboxes I'll fit these, but I'm in no rush to strip it solely for this right now.

I'm still running the rally blocks at the moment. Based on the wear patterns of the tyres I adjusted the camber a bit. One front wheel got a little more camber, and I added more to both rears. Running it in the street, the rear was a lot more mobile, a touch more camber had definitely reduced the traction at the rear. I took a bit of the rear camber off to increase the rear traction again as it wasn't as good to drive.

I've got a set of the tamiya semi-slicks and a set of wheels on their way, I'm hoping that they will be better on the road where the car spends most of it's time. I think the body will need raising slightly to clear the ground with the slightly smaller radius of these tyres.

I have noticed that one drive cup has a bit of oil on it after a good run, so I suspect the rear diff is leaking despite the care I put into building it. Whether it is leaking from the seal or the o-ring in the diff I guess I'll find out when I eventually do pull it apart. I'm not sure whether it is worth buying better o-rings or the aluminium diff covers or not. I'll probably carry on with the diffs built as stock and assess the rate at which they leak in future.

[Toad16v 282]

The wheels arrived today, so I fitted the tyres while lunch cooked and glued them when I finished work. Quick run out in the street with an almost flat battery showed that they have increased grip significantly, super pleased. Will most likely order a second set for the tt01e.

 

 

[Iron Steel 0]

In researching rally chassis, have any of you XV-01 owners compared this to a MF-01X chassis ? and another chassis I just heard about is LC Racing's PTG2 https://www.redrc.net/2021/07/lc-racing-ptg-2-4wd-rally-car/

[Big Jon 684]

22 hours ago, Iron Steel said:

In researching rally chassis, have any of you XV-01 owners compared this to a MF-01X chassis ? and another chassis I just heard about is LC Racing's PTG2 https://www.redrc.net/2021/07/lc-racing-ptg-2-4wd-rally-car/

The MF-01X is a M chassis with limited suspension travel and adjustability, and relatively poor handling in comparison. While I haven't seen an LC in person, looking at the pictures, I assume that it'll have the same issues with stones jamming between the wheels and arms that other long arm cars have, plus poor parts support in the States. 

The XV-01 is still stellar after all these years.

[Toad16v 282]

It is getting darker and damper in the evenings and the GF has just started a uni course that has lectures in the evenings, so I set about a bit of maintenance on the xv01 tonight. Started off stripping the rear gearbox, giving it a good clean and rebuilding with aluminium spacers and the tamiya 4mm spacer set to reduce the risk of the gears stripping. Lots of trial and error with the spacers to reduce the play but leave it spinning freely.

I then took the diff apart as it looks like it's been leaking out one side. Fitted nice new red trf o-rings smeared with green slime and fresh oil - the oil in it was going a bit black, I assume this was from the black o-rings but not too sure. Rebuilding didn't go terribly well. It feels like one of the screws is stripping and doesn't achieve the level of tightness of the other 4 screws. Have ordered new cases and seals and will re-rebuild soon. Couldn't have fully rebuilt as one bearing is a bit crunchy, so am also waiting on some new bearings.

Looks like the aluminium diff covers are now tricky to get hold of in the UK. Had been a bit tempted to buy a set, even though though diff had only leaked past the o-ring rather than past the seal.

[Toad16v 282]

Received the new diff housings and bearings at the weekend so set about rebuilding the rest of the car over the last two nights. Fitted new rubber sealed bearings to the rear diff once the housing was screwed back together and put the rear diff back in.

Moved onto the front diff tonight, pulled everything apart gently and began by fitting the alloy spacers and a pair of 0.3mm tamiya spacers to either side of the gear on the shaft with the pulley to drive the rear to take the play out. In hindsight I regret not shimming the input shaft as that has a fair bit of play too. Fitted another rubber sealed bearings to the front diff. Didn't rebuild this one as it doesn't appear to have leaked at all - probably partly because of the thicker oil.

While the gearbox was out I added some 0.2mm shims to the inner suspension arm pivots, removing the slack from them. So far it's almost back together, just need to fit the covers, front bumper etc. Forgot to actually take proper pictures again.

[Toad16v 282]

Haven't actually driven the XV-01 since September time, but did install the stabiliser bar kit to it. Went with the medium bars front and rear as I felt that it would be easy to replace the rear bar with the thicker or thinner bars to tune the handling a bit rather than try to change the front one. Slightly fiddly to fit, the drop links were tricky to get to the same lengths due to having the little quarter twist in opposite directions but hopefully got them fairly even across each axle.

Today I received a Tamiya 42102 - TRF Special Damper Set after seeing them back in stock at RCJAZ. I'm not bothered about the long damper setup for this car as its mostly running on the road, so felt this was likely to be a decent upgrade. The instructions give examples for setting up for a few cars including the tt01, with spacer, piston and oil reccomendations. Comparing these to the cva super mini dampers which I have fitted to the tt01 the 42102s suggest 2 hole pistons and 500 weight oil vs 400 weight oil for the CVAs. The XV-01 uses super mini dampers too with 2 hole pistons and 900 weight oil, so I'm thinking that the 42102s need a slightly thicker oil, but otherwise are roughly the same. I don't need them to be as stiff as before due to the stabilisers (I could be wrong) so building them with no spacer, 2 hole pistons and 900 weight oil plus the existing XV-01 springs ought to get me in the right ballpark for damping. Fingers crossed!

[ThunderDragonCy 7873]

@Toad16v You really don't need 900wt in 42102. They have much smaller holes in the pistons and much better sealing around the pistons. I would suggest 3 hole pistons and 500cst and see how you go. I run this in my racecars so you really don't want more than that IMO

 

[Pylon80 2618]

1 hour ago, ThunderDragonCy said:

@Toad16v You really don't need 900wt in 42102. They have much smaller holes in the pistons and much better sealing around the pistons. I would suggest 3 hole pistons and 500cst and see how you go. I run this in my racecars so you really don't want more than that IMO

 

I agree about the oil. My personal take on the XV-01 manual calling for 900 oil in the shocks is simply Tamiya wanting to provide only one bottle of oil in the kit. It's s compromise. The shocks would be happier with 400 or 500 (and 3 hole pistons) and the diffs with 3000.

[Big Jon 684]

900 will be very heavy in the TRF shocks, so I'm with the guys above. The TRF shocks are a huge upgrade, and will improve your car a lot once they're properly setup for your application.

[Toad16v 282]

I wish I had read these comments earlier. 2 hole pistons and 900wt oil = way too much damping. Tried 500, the 400, and they're still a bit much with 2 hole pistons. Did test drive it with the 400wt oil, back end was very loose, no body roll but couldn't tell if this was too much damping or the anti roll bars. I guess it was the former! Will change the dampers to 3 hole pistons ASAP.

[Pylon80 2618]

3 hours ago, Toad16v said:

I wish I had read these comments earlier. 2 hole pistons and 900wt oil = way too much damping. Tried 500, the 400, and they're still a bit much with 2 hole pistons. Did test drive it with the 400wt oil, back end was very loose, no body roll but couldn't tell if this was too much damping or the anti roll bars. I guess it was the former! Will change the dampers to 3 hole pistons ASAP.

One more thing regarding the TRF shocks: the pistons are machined very precisely so all the oil flows through the holes with no loss around the pistons. The CVA in comparison have some amount of "leaking" around the sides of the molded black pistons. For this reason TRF shocks will always have more damping with the same oil compared with CVA's.

[ThunderDragonCy 7873]

If the damping still feels too much with 3 hole pistons, you have a couple of options : either go really light on the oil (200cst or something) or get the TRF501X buggy damper pistons. Although only 2 hole, the holes are much bigger. 53978 is the part number. 

[Toad16v 282]

Swapped to three hole pistons and the 400 weight oil. Definite improvement and closer damping to the kit shocks, probably still a bit heavier than stock, but I don't have other oil yet and will try them out to see what it's like.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

[Pylon80 2618]

On 4/3/2022 at 12:31 AM, ThunderDragonCy said:

If the damping still feels too much with 3 hole pistons, you have a couple of options : either go really light on the oil (200cst or something) or get the TRF501X buggy damper pistons. Although only 2 hole, the holes are much bigger. 53978 is the part number. 

You could also redrill the holes with precision bits and obviously measuring the bits with calipers before proceeding and going in very small increment at a time.