Kyosho Ultima SB Dirt Master

[toyolien 4680]

4 minutes ago, BuggyGuy said:

@toyolien This was the brass front block I used:

https://www.rccarshop.co.uk/rdrp0201-rdrp-brass-front-suspension-pivot-block-32g-ultima-rb6-p

The RB6 cross member is UM721 (JConcepts also make one in blue)

The rear hubs I fitted were these: https://www.rccarshop.co.uk/rdrp0199-rdrp-black-aluminium-rear-hub-carrier-set-ultima-rb6-p

But Kyosho themselves make some better ones such as UMW704-0 and UMW704-05 (the trailing digit indicates the amount of toe-in provided) - they are pricey, but the larger bearing they will take would be a big plus.

Much appreciated. I'll probably opt for the Kyosho hubs.

However, the UM721 part number brings up the plastic suspension mount??

[BuggyGuy 1106]

4 hours ago, toyolien said:

Much appreciated. I'll probably opt for the Kyosho hubs.

However, the UM721 part number brings up the plastic suspension mount??

Apologies - it's part UM720B 

[toyolien 4680]

Just now, BuggyGuy said:

Apologies - it's part UM720B 

Fab. Can't find that anywhere in stock. Thanks for taking the time.

[BuggyGuy 1106]

1 minute ago, toyolien said:

Fab. Can't find that anywhere in stock. Thanks for taking the time.

Wheelspin show shadow stock (so must be in at the distie):

https://wheelspinmodels.co.uk/i/225380/

JConcepts version in stock at MBModels:

https://www.rccarshop.co.uk/jc2260-1-jconcepts-kyosho-rb6-rt6-aluminum-front-suspension-brace-blue-p

 

[legacygt777 45]

On 5/16/2023 at 7:35 PM, BuggyGuy said:

 

I don't think the Dirtmaster is original RB5 - it's the SP2/WC version, but any RB5 part will fit. Though be weary of front shock towers - as early RB5 versions were not designed for the big bore dampers - though they will still fit with a couple of spacers, the original RB5 rear shock tower is also a little taller - the Dirtmaster comes with the shorter version that came as standard on the later RB5 cars.

 

I was at a local track and saw the Dirt Master. I used to race and still have the SP2/WC.  There are differences between the two starting with the SP2's Big Bore Velvet Coated shocks.  Also the SP2 has Tungsten Diff Balls for a smoother tranny and differential. The front end of the SP2 is a little wider. The rear ends of both buggies and height are similar but there are more holes on the rear shock towers to bring it lower. FInally, the clutch looks different.  Just thought I'd share my thoughts on the two.  The Dirt Master is a great buggy for that price. 

 

 

 

 

[BuggyGuy 1106]

Bit of an update, as I've now raced mine quite a few times.

- The kit shocks appear to leak with use on bumpy tracks from the caps, I've not found a solution to this so had to more to Xray XB2 shocks (the Kyosho big bores are outrageously priced at the moment)

- Even with aftermarket alloy rear hubs I've  been getting through a lot of rear hub bearings regardless of axle spacers/drive pins/hexes used. I've upgraded to UMW704-0 which uses a much larger outer hub bearing and had no more issues.

- I found the clutch would be hard to set consistently on high grip surfaces, so I fitted UM572 which replaces the plastic washers in the clutch with a larger metal plate and a metal bushing and found this helped a bit to make it more predictable.

- The metal cover for the gear diff is essential if you want to fill the gear diff with oil. The plastic cover flexes just enough to allow oil to leak out.

In terms of performance the car itself is great on grass tracks, and it's fantastic on wet and slippery tracks as well. I raced at a regional recently on astro where it was dry all day, so I used my Associated B6.4, but it rained for the finals so I switched to the Dirt Master and went from 9th to 2nd across the 3 legs of the final. Rear motor cars have a decent advantage on low grip tracks so I'll be taking the car along to future regional races regardless of the surface just in case it rains!

 

[toyolien 4680]

2 hours ago, BuggyGuy said:

Bit of an update, as I've now raced mine quite a few times.

- The kit shocks appear to leak with use on bumpy tracks from the caps, I've not found a solution to this so had to more to Xray XB2 shocks (the Kyosho big bores are outrageously priced at the moment)

- Even with aftermarket alloy rear hubs I've  been getting through a lot of rear hub bearings regardless of axle spacers/drive pins/hexes used. I've upgraded to UMW704-0 which uses a much larger outer hub bearing and had no more issues.

- I found the clutch would be hard to set consistently on high grip surfaces, so I fitted UM572 which replaces the plastic washers in the clutch with a larger metal plate and a metal bushing and found this helped a bit to make it more predictable.

- The metal cover for the gear diff is essential if you want to fill the gear diff with oil. The plastic cover flexes just enough to allow oil to leak out.

In terms of performance the car itself is great on grass tracks, and it's fantastic on wet and slippery tracks as well. I raced at a regional recently on astro where it was dry all day, so I used my Associated B6.4, but it rained for the finals so I switched to the Dirt Master and went from 9th to 2nd across the 3 legs of the final. Rear motor cars have a decent advantage on low grip tracks so I'll be taking the car along to future regional races regardless of the surface just in case it rains!

 

Marvellous update. Which do you think would make the best park/general runner between the Dirt Master and the TD4?

[BuggyGuy 1106]

46 minutes ago, toyolien said:

Marvellous update. Which do you think would make the best park/general runner between the Dirt Master and the TD4?

They are very different cars - both would be a blast in the park. If cost is not an option I'd pick the TD4.

I've really struggled to make the TD4 work on track though - but it's fantastic around the garden!

[toyolien 4680]

15 hours ago, BuggyGuy said:

They are very different cars - both would be a blast in the park. If cost is not an option I'd pick the TD4.

I've really struggled to make the TD4 work on track though - but it's fantastic around the garden!

Thanks for that. I've got both waiting to be built. The Dirt Master was going to be racing in a 'rear motor' class, but my local club has had to close after 30 years. So, now I'm thinking of either selling the DM or keeping it as a general 'park basher'. Not decided yet...

[Kowalski86 3034]

I'm a bit mixed on this kit, I like the idea of an old-school 2wd buggy. At the same time, it looks like an RB5 after the bean counters got to it. Lots of plastic, almost on par with an RTR 

Frankly, I'm not a huge fan of the whole "Let's build a kit for newcomers and nickel and dime them on upgrades" shtick, especially at this price.

[BuggyGuy 1106]

4 hours ago, Kowalski86 said:

I'm a bit mixed on this kit, I like the idea of an old-school 2wd buggy. At the same time, it looks like an RB5 after the bean counters got to it. Lots of plastic, almost on par with an RTR 

Frankly, I'm not a huge fan of the whole "Let's build a kit for newcomers and nickel and dime them on upgrades" shtick, especially at this price.

I think that from a value perspective the Yokomo Rookie Offroard is probably better value - but it's not rear motor. To race a Dirt Master you need to spend at least £100 on upgrades IMO, I've certainly spent a bit more that that at this point. No upgrades needed if you just want to play in the garden though!

[moffman 5752]

I’ve had a bit if trouble with shocks I don’t know if this is me just being a bit ham fisted but the I’ve snapped two of the e-clips and one bent and I didn’t realise and it popped off when I had finished the shock (very annoying) and as you don’t get any spares I just changed the whole lot for tamiya e-clips…..much better! 

[BuggyGuy 1106]

Looks like Team Azarashi have rere'd their old RB5 body (that quite a few people used to use on the 201) for the DirtMaster:

https://www.redrc.net/2023/07/team-azarashi-dirtmaster-aralgo-body/#more-212750

[Kowalski86 3034]

On 7/1/2023 at 4:11 AM, BuggyGuy said:

I think that from a value perspective the Yokomo Rookie Offroard is probably better value - but it's not rear motor. 

From a glance, the RB10 might be the best value since it comes with electronics (though rtr electronics), aluminum big bore shocks, CVA driveshafts, and a pre-painted (if tacky) shell.

The main catch is Team Associated knack for dropping support for models quickly. And you'd need another body to stand out from the other RB10s.

[BuggyGuy 1106]

On 7/6/2023 at 5:59 PM, Kowalski86 said:

From a glance, the RB10 might be the best value since it comes with electronics (though rtr electronics), aluminum big bore shocks, CVA driveshafts, and a pre-painted (if tacky) shell.

The main catch is Team Associated knack for dropping support for models quickly. And you'd need another body to stand out from the other RB10s.

I think parts support should be pretty solid for the RB10 as it shares loads of bits with the DR10 and the SC10 - but I agree that have been a bit shoddy with randomly binning spares off since they got bought out

[legacygt777 45]

On 6/30/2023 at 11:36 PM, Kowalski86 said:

I'm a bit mixed on this kit, I like the idea of an old-school 2wd buggy. At the same time, it looks like an RB5 after the bean counters got to it. Lots of plastic, almost on par with an RTR 

Frankly, I'm not a huge fan of the whole "Let's build a kit for newcomers and nickel and dime them on upgrades" shtick, especially at this price.

If you're going to race on your avg dirt track, the Dirt Master can handle and compete.  It's a proven car for many years.  Plastic on the RTR are usually cheap but the quality of the parts on the Dirt Master are high quality.  I still would change out the shocks.  But the stock shocks were able handle pretty good. Unlike RTR, Kyosho is selling a great kit to build. It's really the best kit to race on dirt for under 200.  I've been racing the RB5 for 13 years in 4 different racing categories. I came in 2nd in the B mains a few weeks ago against modern buggies. I eventually raced my b6.3 but the Ultima was still fun. 

[Kowalski86 3034]

On 8/6/2023 at 11:25 PM, legacygt777 said:

If you're going to race on your avg dirt track, the Dirt Master can handle and compete.  It's a proven car for many years.  Plastic on the RTR are usually cheap but the quality of the parts on the Dirt Master are high quality. 

I'm considering buying one just for bashing around outside and the occasional track run. 

I've owned a Top Cat, Losi XXX, and some flavor of RC10, couldn't run them often due to parts being hard to get. This looks like it's in that same league, definitely a step up from a TRX Bandit.

My main concern is the spacers and figuring out which goes where, and not dropping them!

[BuggyGuy 1106]

1 hour ago, Kowalski86 said:

I'm considering buying one just for bashing around outside and the occasional track run. 

I've owned a Top Cat, Losi XXX, and some flavor of RC10, couldn't run them often due to parts being hard to get. This looks like it's in that same league, definitely a step up from a TRX Bandit.

My main concern is the spacers and figuring out which goes where, and not dropping them!

The DirtMaster was the first kit I've built where a set of vernier calipers was essential - due to all those spacers with no labels.

I've built a lot of cars from a lot of manufacturers and never had to do that before.

[BuggyDad 4475]

Could someone with a Dirtmaster do me a quick favour please? I'm after a few measurements...

First and most importantly the width of the front hub carrier, like this:

Thats my DT-03, on which it's 11mm.

Also the height of the upright in the carrier, like this (both upright and carrier if there are any spacers) :

Finally, the approximate clearance in the carrier from centre of kingpin back to the vertical section behind:

Thanks! 😉😘

[Tamiyastef 1967]

The first is 12mm

The second is 14 mm

Third is 15,7 mm

Last one is 12,7 mm

[BuggyDad 4475]

1 hour ago, Tamiyastef said:

The first is 12mm

The second is 14 mm

Third is 15,7 mm

Last one is 12,7 mm

Thats wonderful. Thank you. I think I can be fairly confident then that the carrier will fit into the DT-03 arm, so carrier plus upright as a unit will drop in. Likely no filing, 1mm spacer. Bonza!

I haven't the Blitzer with me but I'd be surprised if the same wasn't true there.

The upright and carrier both feel like strong plastic I assume?

Righto. I'll stop derailing this thread! 😘

[Tamiyastef 1967]

16 minutes ago, BuggyDad said:

like strong plastic

Yep the reinforced type feel 

[SlideWRX 785]

On 10/24/2023 at 2:02 PM, BuggyDad said:

Thats wonderful. Thank you. I think I can be fairly confident then that the carrier will fit into the DT-03 arm, so carrier plus upright as a unit will drop in. Likely no filing, 1mm spacer. Bonza!

I haven't the Blitzer with me but I'd be surprised if the same wasn't true there.

The upright and carrier both feel like strong plastic I assume?

Righto. I'll stop derailing this thread! 😘

Well, You might stop, but the rest of us... be sure to detail your results in this thread:

 

[BuggyDad 4475]

9 minutes ago, SlideWRX said:

Well, You might stop, but the rest of us... be sure to detail your results in this thread:

 

Ah. Oops. I've pretty much duplicated that thread with my other one. I now realise I had seen it before. I wonder if they can be combined somehow?