OHOs DT02 HB speed project!

[Oh How Original 126]

Bought originally just for something for myself and my Dad to run together.

It's also a convertible now, since bashing ripped the roof off anyway.

First pictures are still brushed, alongside my Dads HB.

 

 

 

 

 

 

 

 

 

 

 

Ran brushed to begin with, but have since put a HobbyWing ESC and 4000kv motor in, needless to say, it's fast.

I would like to get a cheap speedo of some kind to see how fast I can make it, I'm no speed expert, so not aiming for crazy numbers, maybe aim for 30mph to begin with, which I think is fairly easily doable.

Before...

 

After

 

 

First run with the BL system, much much faster, just a little urban shakedown.

 

Wheelies very easily.

 

 

 

 

That's all for now.

[Carmine A 2046]

NICE!!! Inspires me to get the dust off of my HB, and let her rip. I haven't gone Brushless - YET, but I'm sure it's coming! 

My go-to not expensive yet fast and powerful Brushless ESC has always been the Hobbywing WP BL120. Been reliable, and is one of the few that are both Sensored and Sensorless compatible. Someone's always got them on sale, they CAN handle 6S (even though they say 4S, I've run 6S in my Axial Wraith for over 5 years!!). And I believe down to an 8T Brushed Motor or 6600kv Brushless Motor!!! 😳

The DT-02 is a STOUT and very underrated Chassis!! 😎  The Gearbox can handle an unreasonable amount of power... They just needed added weight in Front. That made a dramatic difference in my handling! 

[Oh How Original 126]

On 1/28/2021 at 3:34 PM, Carmine A said:

NICE!!! Inspires me to get the dust off of my HB, and let her rip. I haven't gone Brushless - YET, but I'm sure it's coming! 

My go-to not expensive yet fast and powerful Brushless ESC has always been the Hobbywing WP BL120. Been reliable, and is one of the few that are both Sensored and Sensorless compatible. Someone's always got them on sale, they CAN handle 6S (even though they say 4S, I've run 6S in my Axial Wraith for over 5 years!!). And I believe down to an 8T Brushed Motor or 6600kv Brushless Motor!!! 😳

The DT-02 is a STOUT and very underrated Chassis!! 😎  The Gearbox can handle an unreasonable amount of power... They just needed added weight in Front. That made a dramatic difference in my handling! 

 

I am finding the handling to be very good actually, the tyres let it down slightly, but lets be honest, the whole kit is £85 (in the UK) so that can't be complained at.

Perhaps some weight would help this, but I am not racing anyway.

Mine is actually the 60a version as well, since I can only fit a 2s pack in the chassis, without major modification.

But it is a very good ESC so far, I shall have some video footage posted up soon, it will make you want to go brushless

Also, check the dimensions of your 120 if you plan to use it, against the 60, because the 60 only just fits in that gap I have it in.

[Carmine A 2046]

1 hour ago, Oh How Original said:

 

I am finding the handling to be very good actually, the tyres let it down slightly, but lets be honest, the whole kit is £85 (in the UK) so that can't be complained at.

Perhaps some weight would help this, but I am not racing anyway.

Mine is actually the 60a version as well, since I can only fit a 2s pack in the chassis, without major modification.

But it is a very good ESC so far, I shall have some video footage posted up soon, it will make you want to go brushless

Also, check the dimensions of your 120 if you plan to use it, against the 60, because the 60 only just fits in that gap I have it in.

I've got a 10BL-60 too, I'll try the fit.... 

Perhaps because I've only got Soft Pack Lipos from my Crawlers. I have no problem fitting a 3S in my Holiday Buggy. It's a 2200 MAh, more than enough for how it's set up now.

[Oh How Original 126]

On 1/30/2021 at 11:30 PM, Carmine A said:

I've got a 10BL-60 too, I'll try the fit.... 

Perhaps because I've only got Soft Pack Lipos from my Crawlers. I have no problem fitting a 3S in my Holiday Buggy. It's a 2200 MAh, more than enough for how it's set up now.

 

Actually I didn't think about my small crawler packs, I have quite a few 3s ranging from 1500-2900, I could easily squeeze a 1500 in there, just for a few speed runs.

That is thought provoking, but naturally, I am off work today so it's raining, no testing today.

My friends Timberwolf hit 37mph the other day though, so I feel this is around 38-39mph as it's just very very slightly faster.

[Carmine A 2046]

3 hours ago, Oh How Original said:

 

Actually I didn't think about my small crawler packs, I have quite a few 3s ranging from 1500-2900, I could easily squeeze a 1500 in there, just for a few speed runs.

That is thought provoking, but naturally, I am off work today so it's raining, no testing today.

My friends Timberwolf hit 37mph the other day though, so I feel this is around 38-39mph as it's just very very slightly faster.

Yeah, you just want to avoid smashing full speed into a Curb or something!!! 😜😁  Personally I've had no problems running Soft Packs in Buggies.

[mud4fun 1696]

Great pictures and lovely HB's 

My daughter's DT02 does 28mph on a brushed 19T Reedy (17t pinion) and 7.6v 2S so with a brushless and 3S I would have thought it would go alot faster than 30mph? Surely 40mph+?

Mind you my daughter is struggling to control hers at its current speed so I don't think she'd want hers any faster LOL, it already wheelies everywhere if she is not careful with the throttle  (and that is with 90g of lead sheet wrapped around the front bumper!)

[Exit13 673]

Nice! Great photos. Looks like fun. Now I want one!!

[Oh How Original 126]

Gave the Holiday buggy it's first speed test, footage will follow in which you'll see all it wants to do is flip over, managed to hit 42mph though which on a 2s I think is quite impressive... I think one of my shock shafts is bent because they are really stiff and don't want to move, I think that contributed to the fact it wanted to flip over so much, definitely going to lower it, also going to make some attempt at aerodynamics, I kinda want to hit 50mph now and I will be extremely happy.

I was expecting about 32-33 based on my friends Timberwolf maxing out at 37.

It did have just a smidge more to give though, but between cars, wagons, flipping over and bumps and skidding, I didn't get what I'd consider a flat out clean run, ideally want to hold it flat for a good 5-10 seconds, I do have another spot to try though.

The big question, what's the fastest Holiday buggy known?

 

[Oh How Original 126]

The footage of the speed run as promised, super happy.

From my research, the fastest Holiday buggy is 47.3.. So 48 is now my current goal, if that is achieved, I will aim for 54, so I am in the top ten fastest Tamiyas in the world  

 

 

[Carmine A 2046]

Damp Road was taking a chance!! Good job holding on. 👍👍 Good speed there! Can't wait until I can get one of those Speed checkers, and start measuring mine.

[Oh How Original 126]

2 hours ago, Carmine A said:

Damp Road was taking a chance!! Good job holding on. 👍👍 Good speed there! Can't wait until I can get one of those Speed checkers, and start measuring mine.

 

Yeah man, I was quite surprised, super happy with 42, I think it has maybe another 1-2mph in the current set up, even more if I lower it down, get the shocks set up right and figure out a custom motor mount for larger pinions, but right now I can't.

Although I have just ordered some front hex adapters, so I can run some 10th scale 'normal' buggy tyres and wheels, I think they are 1-2mm taller and they might balloon slightly more too which might push it to 45mph.

[mud4fun 1696]

My Thundershot gets 45mph from a 13T 36K rpm brushed motor and a 7.4v 2S and my Schumacher Cougar gets 50mph from same motor but with a 7.6v LiPo shorty but with slightly taller gearing. Both run dead true and straight with no handling issues at all at those speeds, no wheelies, no vibrations and no instability, they can both follow a joint in the tarmac for hundreds of feet at those speeds. Both run 2.2" buggy tyres and in fact the Thundershot got 45mph on large medium compound pin spikes. Neither of those speeds is on the tallest gearing possible in the buggies, actually nearer mid gearing. You'll be surprised just how fast a basic Tamiya can go. However the difference between fast and wild and fast and in control is a whole different thing 

 

[Oh How Original 126]

18 hours ago, mud4fun said:

My Thundershot gets 45mph from a 13T 36K rpm brushed motor and a 7.4v 2S and my Schumacher Cougar gets 50mph from same motor but with a 7.6v LiPo shorty but with slightly taller gearing. Both run dead true and straight with no handling issues at all at those speeds, no wheelies, no vibrations and no instability, they can both follow a joint in the tarmac for hundreds of feet at those speeds. Both run 2.2" buggy tyres and in fact the Thundershot got 45mph on large medium compound pin spikes. Neither of those speeds is on the tallest gearing possible in the buggies, actually nearer mid gearing. You'll be surprised just how fast a basic Tamiya can go. However the difference between fast and wild and fast and in control is a whole different thing 

 

I just need a better location, the road is too bumpy, but I was eager to test my new gps lol.

[mud4fun 1696]

27 minutes ago, Oh How Original said:

I just need a better location, the road is too bumpy, but I was eager to test my new gps lol.

Yeah, we use a gated off old car park next to our local rec ground, about 600 foot long but only with about 300 feet of decent surface, the rest is all moss or badly pot holed etc. But it is nice and quiet, and we don't have 1:1 cars driving past every 2 mins. We barely see anybody else down there so it works out well. It also has the added benefit of a 200 foot long joint in the tarmac straight down the middle which we use as a guide to keep in a dead straight line  

We are quite lucky really, it is only a mile down the road so we can wonder down there whenever we want really although we normally go down on Sunday mornings when it is very quiet.

[Oh How Original 126]

7 hours ago, mud4fun said:

Yeah, we use a gated off old car park next to our local rec ground, about 600 foot long but only with about 300 feet of decent surface, the rest is all moss or badly pot holed etc. But it is nice and quiet, and we don't have 1:1 cars driving past every 2 mins. We barely see anybody else down there so it works out well. It also has the added benefit of a 200 foot long joint in the tarmac straight down the middle which we use as a guide to keep in a dead straight line  

We are quite lucky really, it is only a mile down the road so we can wonder down there whenever we want really although we normally go down on Sunday mornings when it is very quiet.

 

I have a very empty road quite local, maybe 5-6 miles away, which could be a good location, the road isn't super wide, but it's just grass either side, so I don't think getting out of control would result in anything too extreme in terms of damages.

It's also very good visibility and nobody really goes down it besides farmers, but the surface is still quite nice too, fingers crossed it turns out a good location.

If not, there's two more potentials, both under 10 miles from home.

[Oh How Original 126]

So I picked up some of these bearing to 12mm hex conversion hubs from Fastrax.

Unfortunately, they are quite poor, not a very good fit on the axle and not a very tight fit on the hex of the wheel, tried for several different wheels, they were all loose, my guess is it seems they are machined to a about 11.5mm then they 'hope' anodising adds the 0.5mm... It didn't!

I took a quick picture with the new wheels and tyres mounted, unfortunately until I find a fix for the hubs or something, I will be running stock fronts and new rears.

 

 

I think it looks really cool though!

 

 

The extra height should definitely help me.

 

 

I think set about work on the shocks, I have shortened the rear by 8mm, then added a 5mm bump stop, so they have very limited travel, I am yet to do the fronts, but will get around to it, picture below demonstrates the difference.

 

 

The current wheel/tyre set up.

 

 

After doing some more testing tonight, a new body and body posts for the rear have been ordered, because, well....

 

 

 

And I am very happy and proud to now officially be on the speed run list.

 

[mud4fun 1696]

@Oh How Original the fastrax adaptors work great. My daughter has them on her DT02 with schumacher race wheels and has done hundreds of laps of racing on them with no issue even with a hot motor and HV LiPo.

However they are not a straight fit, you have to fit additional parts, shims and potentially drill out wheels etc to make them work.

The DT02 required a standard 5mm washer (greased) fitted behind the fastrax adaptors, then you must fit a greased shim in front. The 12mm hex drive Schumacher wheels needed a 5.1 - 5.2mm hole drilling through their centres so the wheels ran smoothly and cleared the axles but not large enough to introduce slop. Then you need to carefully tighten the nyloc until the wheel rotates smoothly BUT has no end float. We also used threadlock on the nut. Remember that normally a hex drive wheel is clamped to the drive hex, with these adaptors the wheel sits loosely on the adaptor and is only prevented from moving by the close contact of the nut. Hence the reason we use a greased 10x5mm (or 8x4) shim (schumacher) between nut and wheel. The schumacher slim race wheels now rotate perfectly on my daughters DT02 and there is no slop at all. We also fitted quality bearings as the supplied ones are junk.

Those adaptors are not designed for fitting without any fettling.

PS. I wouldn't read too much into that list of fastest Tamiyas...... The stated rules about videoing the speed run means many people can't be bothered. My buggies have run faster than most of those in that list and on brushed motors with NiCd batteries but I just couldn't be bothered spending ages trying to do a video. I just wait until we meet up and my brushed motors wupp their brushless and leave them perplexed  

We can all get a buggy to go 50+mph in a straight line, the real gains is making it go around a corner under power.  

And don't get me wrong, I enjoy doing the speed runs, I do GPS speed tests on all our cars regularly but for me it is mainly to test setup and compare gearing etc. The fact I can do 55mph in a Cougar on a brushed motor and 2S LiPo is largely irrelevant because I can only use that gearing for 1 minute before the ESC/motor overheat. For general running I use much lower gearing, typically max 35mph for racing on our garden track.

It is useful for setup though, if as with my Thundershot, it can do 40mph in a dead straight line over rough tarmac for 300 feet then you know your toe-ins are good. My daughters Terra Scorcher out of the box was utterly dire, was fighting her and completely unable to maintain an arrow straight line even at 25mph. We fixed the front and rear toe-ins and added negative camber and it tracks perfectly now.

Just be aware the GPS speed testing can become addictive to the point you change your car to get faster and faster speeds but end up with a car you can't use for daily bashing or fun. I have been there and done that. In the end I reverted the car back to bashing spec as it was getting no use as a drag car. 

[Oh How Original 126]

That's some good information about the Fastrax adapters, it really seems rather stupid they didn't just make them correctly in the first place though, I guess it's a budget brand and all, I kinda expected them to need something, because of the unconventional way the Tamiya fronts rotate.

Already drilled the wheels out so they do slide on, I will have a look for those shims and get some ordered.

That will open things up a bit for me with regards to wheels and tyres certainly.

Although doing some reading up a bit more on GPS and a few people have said they sometimes read a tiny bit low.

One chap put two GPS's on his car, his Traxxas one read 65 and the SkyRC read 63, not a huge amount out, but still, when all I need is a couple of mph, that couple of mph might be screwing me lol.

Might have to order a Speed Flea and run both, just to be sure and check them against each other.

And yeah this HB won't be used for bashing again, once I beat the current HB WR, it will either retire or continue getting faster.

[mud4fun 1696]

Thanks.

The shims I used were left over from my Schumacher Couger new build (at xmas), I'll go measure them later and let you know what size they were. I don't think you can use a plain washer for those. Pretty sure I tried that and they were too thick and I ended up with no thread left to engage the nyloc, even more critical with the adaptors as the wheel is spinning against that nut so it is more likely to come off (hence the reason I also used threadlock on them. I did use a plain 5mm washer behind the adaptor though. I made sure to use a light grease on the washers and shims to make sure they didn't bind up.

Yeah I know what you mean about those adaptors but in their defence, I think Fastrax originally did them for shelf queens rather than runners and they are not specific to a DT02 either so axle lengths differ from buggy to buggy by a 1mm or two so I forgive them the need to do a bit of fettling to make them work. As you say, they really open up the wheel options. My daughter loves the black Schumacher race wheels. I just ordered her a set of rears so they match the fronts.

Hehe, I remember many years ago, 2002'ish I think, I got into doing speed testing and modifying the car to go faster and faster. It is VERY addictive! I ended up lengthening the wheelbase of a Thundershot but hacking up and adding extra plates into the tub so I got a 300-350mm wheelbase, lowered the car right down so it was slammed to the deck and I was using a 9.6v NiCd (this was pre-LiPo and pre-brushless, well certainly they weren't at all common if you could find them at all in LHS). I also had a HUGE ESC and even had a fan mounted on it which was really rare back then. I think the fastest I got from my Thundershot back then was 47mph. It was considered really quick at the time but now with brushless and especially liPo, speeds have increased significantly. 

I am tempted to put the drag racer back together but this time use modern electronics. The ESCs, RX's and servos and LiPo batteries are so much lighter now my Drag buggy would probably be 300g lighter than it was back then although I think the weight actually kept it on the ground, I certainly didn't have the wheelying and flipping issues that the DT02's have (including my daughters.....)

We were using a Police radar gun to measure speeds because back then we didn't have the little SkyRc GPS units that we do now. After you mentioning the inaccuracy I suspect the police radar gun may have been more accurate!  

Anyway, have fun and I look forward to following your progress 

 

[Oh How Original 126]

Episode 2 of the world record Holiday buggy build.

We hit a new record, not by a big margin, but it is forward progress!

UK rain and wind isn't making it easy at the moment, but we will hit the world record, I have no doubt!

 

[Thommo 1217]

 

Does it specifically have to be a Holiday Buggy ?  You know it would go faster with a Sand Viper body especially if it was red !

The front of the Holiday Buggy lifts at speed once a bit of airflow gets under those guards.

[Oh How Original 126]

4 hours ago, Thommo said:

 

Does it specifically have to be a Holiday Buggy ?  You know it would go faster with a Sand Viper body especially if it was red !

The front of the Holiday Buggy lifts at speed once a bit of airflow gets under those guards.

 

Yeah, it's what I want to do it with, it's just a bit of fun really.

Anyone who has the money could go and buy an Arrma or something and plug batteries in and go 80+

But to me that's not fun, overcoming the issues you face as you go along is the fun part of it for me  

I could also just put a 3s in it, but again, it kind of takes away some of the fun and challenge, but as I previously mentioned, I might go 3s once I am 'finished' with where I want to get to on 2s, just to see what the gearbox will take.

[Oh How Original 126]

 New body and mounts fitted today, along with a Schumacher mini wing, thanks to DMS Racing for helping me with one that would fit between the arches.

Then tested out my new Zeee 2s 7200 80C and I have set a new PB with it AND an unofficial world record and that's going very slightly uphill as you'll see in the coming video and episode 3 of the WR HB project 😄 

And my long suffering girlfriend has just said I can buy some bits and pieces on her, expecting it to be a few connectors and whatnot, I asked what my budget is and she said £299... New motor and ESC ordered for this, also on the lookout for some more buggy wheels and tyres that will fit it.

I also really want to try the current set up on perfectly flat and smooth ground sometime, with no wind.

 

 

 

[Problemchild 2149]

Good stuff 

I’ve ordered a gps bike Speedo to see how fast my monster beetle goes

then I’ll see how fast my TT02b is 

 

JJ