Nitro - a slippery slope indeed!!!!!

[LeftyAl 165]

Not sure if this is the right spot (mods please move as needed), but I dipped my toe into the world of nitro last week. There is a bit of a back story to why, so bear with me.

Once or twice a year, I head to my brother in laws for a week and we race modified Himoto buggies on his sprint car track (a.k.a his drive way) each lap is 50m on the ideal line which each corner being unique. The track condition tends to get better towards the end of week. So... with all the usual BS talk in the lead up to the next event in October, we we talking about the number of people he gets there. This year we are expecting 20+ cars with most of them in sprint car form and family members/ friend heading out to enjoy the night.

We have some demo cars lined up (not in Sprint car config), HPI Savage XS, Kyosho Javelin, 1/5 Baja and a few randoms coming in. So these cars go out and cut some laps between rounds to keep the non racers entertained.

An ebay seller had a 20% off sale on HSP nitro buggies. I know they are pretty crappy (have had electric ones before), but at AUD $198 delivered I figured it was a good chance to take, and adding some nitro noise and smoke to the night would be good thing. it has a VX18 and 2 speed in it, so it should be a heap of fun on the track.

I spent the last week or so learning about Nitro on the fly. So far we have gone though a 1.5L of fuel. The HSP weak point is definitely the lower arms. I'm sure if I looked at one the right way it would break... so the lesson here is to keep it straight and not hit anything. Other than a rock getting into the centre gear box and taking all the teeth off 2nd gear, it has been a reasonable journey so far.

My son is already wanting a HPI Firestorm, and if it is half as tough as my HPI Savage XS then it will be a great car.

Have been into RC cars for a 20+ years and this is the first nitro, sorta wishing I had gotten into it ages ago.

I'll put together a thread on how we mod the cars and the the race night. Just need to sort out some pic hosting (would appreciate suggestions on good options).

So, if you are thinking of Nitro but arent too sure. I think it is working taking a chance on. You just might get hooked on the smell and sound.

[Juggular 5229]

That sounds fun.  

Sorry to hear about the gear being chewed up. (I always wondered why nitro gears are often exposed)  

 

[KEV THE REV 2440]

11 hours ago, LeftyAl said:

You just might get hooked on the smell and sound.

Yes indeed !!

[LeftyAl 165]

7 hours ago, Juggular said:

That sounds fun.  

Sorry to hear about the gear being chewed up. (I always wondered why nitro gears are often exposed)  

 

Thanks mate, I don't mind doing repairs.  I enjoy finding out what makes them work. The 2 speed always interested me and now I can pull one apart to see what makes it tick.

[Juggular 5229]

4 minutes ago, LeftyAl said:

Thanks mate, I don't mind doing repairs.  I enjoy finding out what makes them work. The 2 speed always interested me and now I can pull one apart to see what makes it tick.

Well, you might enjoy Terra Crusher!  2 speed + reverse is cleverly done.  

I'm glad you are enjoying nitro.  I love the simplicity of electric. But the sound and smoke makes it a totally different beast.  

 

[LeftyAl 165]

I am tending to think each has their own type of simplicity.

Electric is great as you flick a switch and off you go, but the technology in the ESC/motor/battery is pretty cool. 

Nitro motors are so basic in design, but the flip side is they can be fussy to tune. But when you get the tune right and hear that engine scream... well that is just an awesome sound.

[Superluminal 4174]

On 8/29/2019 at 3:24 PM, Juggular said:

That sounds fun.  

Sorry to hear about the gear being chewed up. (I always wondered why nitro gears are often exposed)  

 

No idea - considering they are always covered in oil residue from the exhaust which attracts grit. I have this on my kyosho mantis - fortunately the gear teeth on the bell clutch drive seem to be made of a very tough reinforced plastic. Maybe its to do with the heat from the engine not being ideal for attaching a plastic moulded gear cover.

[LeftyAl 165]

I replaced 2nd gear and set the boy off for a drive. Took a while to work out I had set the 2nd gear clutch grub screw too tight and it wasn't engaging. So fixed that up. back out for a run and 1st gear stripped. The driveway is very clean so figured something was up.The huge amounts of ground plastic showed that the motor had moved and not only stripped the gear, but was also chewing it's way through the support post for the fuel tank sub frame. (away from the centre gears).

Tuned that up properly and no gear chewing issues now. I suspect it was the motor moving that also took out 2nd gear.  But I am enjoying the the journey, didn't realise that you can tune when second gear is engaged... or lock it out if you want. 

I now have a spare gear box and a set of steel centre gears on order.

 

[DK308 219]

I would not get into anything HPI currently. It is next to impossible to get parts. I know a local company has some plans for reviving HPI, but I can say that even with that, parts are impossible to get.If you want something in that price range, look into the Hobao rigs.Good quality and plenty of parts.

[LeftyAl 165]

Thanks DK308, am aware of HPI's situation and the deal with Vestergaard Group. Ebay AU has a fairly good range of HPI gear at present. Will be a little while before I look at another nitro car and will take your advice to check out Habao when the time comes.

 

[acprc 1602]

Sadly unless you are buying a later TG10 Mk2 most of the Tamiya range has parts that are very very hard to get now.

[markbt73 6238]

On 8/29/2019 at 7:24 AM, Juggular said:

That sounds fun.  

Sorry to hear about the gear being chewed up. (I always wondered why nitro gears are often exposed)  

 

I've always assumed it's because it's too hard to seal a cover onto the flywheel/clutch assembly. At best, you could shield it, but then you have the problem where dirt and crud gets into the cover, but can't get out again. Heat buildup may be an issue too. Better to leave it open.

I used to really enjoy the nitro cars, more so than I thought I would. But now, living in a fairly quiet neighborhood, with no easy access to an open place to run them, I've gotten rid of all of them that I used to have. Maybe someday I'll go back to them... I'm certainly more interested in tuning a nitro engine than I am in pushing buttons and setting jumpers on a brushless ESC.

[LeftyAl 165]

7 hours ago, markbt73 said:

I've always assumed it's because it's too hard to seal a cover onto the flywheel/clutch assembly. At best, you could shield it, but then you have the problem where dirt and crud gets into the cover, but can't get out again. Heat buildup may be an issue too. Better to leave it open.

I used to really enjoy the nitro cars, more so than I thought I would. But now, living in a fairly quiet neighborhood, with no easy access to an open place to run them, I've gotten rid of all of them that I used to have. Maybe someday I'll go back to them... I'm certainly more interested in tuning a nitro engine than I am in pushing buttons and setting jumpers on a brushless ESC.

In my case the gear was chewed up as the motor had moved. I with you on why the gears are exposed. apart from stopping building up (dirt, crud and heat),  the mesh is so big that most small junk will just blow straight through. 

I was always anti nitro (noisy, dirty, slow), but am glad I got one. Hopefully you find a place where you could run one and get back into it.

[DK308 219]

12 hours ago, LeftyAl said:

In my case the gear was chewed up as the motor had moved. I with you on why the gears are exposed. apart from stopping building up (dirt, crud and heat),  the mesh is so big that most small junk will just blow straight through. 

I was always anti nitro (noisy, dirty, slow), but am glad I got one. Hopefully you find a place where you could run one and get back into it.

Slow?

I've seen nitro cars with enough juice to do standing backflips.

My Hyper VS with a modded LRP .32X Comp spec 4 will give any 6S buggy a run for it's money. That thing has been tested to well over 5 hp.

If your nitro car is slow and lack response, you're doing something wrong.

[LeftyAl 165]

Yes slow, all the ones I have seen take ages to accelerate, maybe I am too used to brushless/lipo setups. Once a nitro gets into their powerband they are good, but that band is pretty narrow. My experiences have been that brushless/lipo is hard to beat. I expect that there are some Nitro's that can keep up, but it is hard to argue with the flat torque curve of a brushless motor. Horsepower is good, but torque is king for acceleration. Pre-brushless I had a 12X3 in a TA03 that showed more than a few nitro cars up.

My brushless Savage XS is box stock and can do a backflip on a 2S battery.  All my speedway buggies run a wheelie bar as even with a 3000kv motor they wheelstand, Things get real interesting when we use the 4800 and 5600Kv motors.

The nitro buggy I bought came with some stock off road tyres, after about 12 or so tanks running on a long concrete driveway (with half of those pretty damned quick) they finally wore out. I have used the same tyres on a brushless 4000Kv buggy and got 2 batteries run out of them for the same wear.

Sure there will be fast nitros out there, but I have a $195 car and I do not expect it to compete with my brushless cars. I don't think I am doing anything wrong... but it does sound and smell better.  

[DK308 219]

22 hours ago, LeftyAl said:

Yes slow, all the ones I have seen take ages to accelerate, maybe I am too used to brushless/lipo setups. Once a nitro gets into their powerband they are good, but that band is pretty narrow. My experiences have been that brushless/lipo is hard to beat. I expect that there are some Nitro's that can keep up, but it is hard to argue with the flat torque curve of a brushless motor. Horsepower is good, but torque is king for acceleration. Pre-brushless I had a 12X3 in a TA03 that showed more than a few nitro cars up.

My brushless Savage XS is box stock and can do a backflip on a 2S battery.  All my speedway buggies run a wheelie bar as even with a 3000kv motor they wheelstand, Things get real interesting when we use the 4800 and 5600Kv motors.

The nitro buggy I bought came with some stock off road tyres, after about 12 or so tanks running on a long concrete driveway (with half of those pretty damned quick) they finally wore out. I have used the same tyres on a brushless 4000Kv buggy and got 2 batteries run out of them for the same wear.

Sure there will be fast nitros out there, but I have a $195 car and I do not expect it to compete with my brushless cars. I don't think I am doing anything wrong... but it does sound and smell better.  

You need to experience some proper tuned nitro cars then, with powerful engines.

Making that little XS doba backflip is not exactly hard.

My MTA4 .50 which is a 6+ kg 1:8 rig that is even bigger and heavier than the Savage 5.9, will go straight on its roof just by the blip of the throttle.

My Hyper VS will outrun my Typhon on 6S both on acceleration and top speed.

Good tuning, a powerful engine and a proper clutch. Those things make a world of difference. 

Yes, a poorly tune Traxxas nitro or the like is an absolute dog. But if you get the chance, try a rig with a properly powerful setup. It will do all the same wheelies and speed runs the brushless stuff will do

I own and run both so it's not because I don't like brushless and prefer nitro. It is what it is and there are some seriously stout nitro stuff out there. 

[LeftyAl 165]

As you have shown , it all comes down to money, spend enough on the right gear and you can go fast.... regardless of your power plant choice. We can go backward and forwards on this for pages and pages and the end result wont matter.

As long as we are enjoying what we do, that is all that matters. 

[DK308 219]

5 hours ago, LeftyAl said:

As you have shown , it all comes down to money, spend enough on the right gear and you can go fast.... regardless of your power plant choice. We can go backward and forwards on this for pages and pages and the end result wont matter.

As long as we are enjoying what we do, that is all that matters. 

Completely agree:)

I will say that it does not have to be stupid expensive. If you shop around, you'll be able to get a Hobao VS roller, an LRP .32X Comp  Spec 4 and a remote system for close to what an Arrma Typhon 6S + two 6S packs will cost you.

It is generally cheaper to get into fast brushless, especially in 1:10 stuff, that's true, but it's not the same as there's no fast nitro stuff.

The issues I suppose with nitro is, that there's no real corners to be cut. If the engine gets too poor and cheap it simply does not run well. It seems easier to build a no-name brushless motor and use those with some off brand esc. That is usually the case with a lot of the really cheap stuff.

There's one exception though. The Himoto Python XV3/Redcat Tornado S30. That thing is 55mph capable out of the box. You get a lot of 1:10 RTR nitro buggy with that one, and it will run with a lot of brushless stuff in the same price range. The SH.18 engine is a surprisingly good mill. Same goes for the T2M Pirate Nitron. Not as fast on top, but a strong runner that will run with most bashing style 1:10 stuff.

Granted, they are nothing like my TRF503 on a track, but that's not really a point of reference. But for the beach, the park, the skateboard track, or just the rc track for fun, those two nitros will hang with most things when tuned properly.

[LeftyAl 165]

I was checking out the Himoto Python last night. Apart from the motor and suspension it looks very similar to my HSP Rage . I know the HSP/Himoto/Redcat all share parts, but do you know if the parts are all made in the same place? i.e are they all the same quality? The Himoto Syclone looks like my HSP, but my HSP has the 2 speed with the VX18 engine. Syclone Pro has 2 speed with the SH18 engine.

The reason I ask is I find that HSP lower arms (front and rear) are a weak point. It doesn't take much to break them where the suspension pin goes through. I think the plastic is too brittle and doesn't have any flex to absorb impact.

[DK308 219]

9 minutes ago, LeftyAl said:

I was checking out the Himoto Python last night. Apart from the motor and suspension it looks very similar to my HSP Rage . I know the HSP/Himoto/Redcat all share parts, but do you know if the parts are all made in the same place? i.e are they all the same quality? The Himoto Syclone looks like my HSP, but my HSP has the 2 speed with the VX18 engine. Syclone Pro has 2 speed with the SH18 engine.

The reason I ask is I find that HSP lower arms (front and rear) are a weak point. It doesn't take much to break them where the suspension pin goes through. I think the plastic is too brittle and doesn't have any flex to absorb impact.

I know the HSP, Redcat and Himoto stuff is virtually identical. I do also know there are some slight differences on some models. You can try and find some exploded views of the Python and then compare them to the exploded view of your HSP. There might be a difference, because I know for a fact that some things are made to the individual brands specifications. Out of the five brands that include HSP, Himoto and Redcat I believe HSP is in the middle and Himoto and Redcat share the first place. Himoto and Redcat are the two most alike in the bunch if you will. Not entirely sure if your engine is actually a rebranded SH or if it's something else. It might be a Force.

[LeftyAl 165]

Thanks, I'll try some Himoto/Redcat branded parts and see if there is a difference.

[mtbkym01 4870]

The VX engines arent the same as SH. SH are quite good quality (I believe they are Golden Lion manufactured, which also manufactured some of the larger 1/8 LRP and Nosram engines) The VX on the other hand will run ok, but aren't very consistent, have a very small tuning window, and develope air leaks very easily which result in a very inconsistent tune.

[LeftyAl 165]

6 hours ago, mtbkym01 said:

The VX engines arent the same as SH. SH are quite good quality (I believe they are Golden Lion manufactured, which also manufactured some of the larger 1/8 LRP and Nosram engines) The VX on the other hand will run ok, but aren't very consistent, have a very small tuning window, and develope air leaks very easily which result in a very inconsistent tune.

Thanks mate, I wasnt expecting really great gear from HSP... but at least this way I'll get lots of practice in tuning. 

[DK308 219]

18 hours ago, LeftyAl said:

Thanks, I'll try some Himoto/Redcat branded parts and see if there is a difference.

There's a set of Himoto alloy A arms available for the Python XV3. If your rig shares A arms with the Himoto, you can try those. These are the part numbers.

Front: 166019

Rear: 166021

[markbt73 6238]

On 9/3/2019 at 5:43 AM, LeftyAl said:

Yes slow, all the ones I have seen take ages to accelerate, maybe I am too used to brushless/lipo setups. Once a nitro gets into their powerband they are good, but that band is pretty narrow. My experiences have been that brushless/lipo is hard to beat. I expect that there are some Nitro's that can keep up, but it is hard to argue with the flat torque curve of a brushless motor. Horsepower is good, but torque is king for acceleration.

Getting the clutch set right is the key to acceleration in the nitro cars. If it engages too early, the engine won't have a chance to build up revs before it has to start moving the car, and it will bog down and accelerate slowly until it gets up into the power band. if there is a spring adjustment on the clutch, try setting it stiffer, or if there's no spring, get an extra set of clutch shoes and cut about 1/3 of the length off the trailing edge. This makes them lighter, so it takes more centrifugal force (higher revs) to engage it. It can make a HUGE difference in the acceleration from a stop. (still probably no backflips, but much punchier.)