Hpi savage?

[gti power]

I picked up a savage 25 today after already having a savage 35, the engine block has 35 on it though is this right?  I can't see any marking on the engine from my 35 to compare.

 

Im in the process of tuning it but after failing to realise the engine was working itself loose on the chassis I destroyed the 48 tooth spur gear. 

 

I decided to swap the engine over to my 35 and continue turning so I can also strip and clean the chassis on the 25.

My 35 has a 52 tooth spur gear,  I believe this will allow it to accelerate/wheelie quicker? Shall I order a 52 tooth for the 25 also (provided that it's a 25).

Also it was missing a carburettor return spring,  can anyone help with a part number for this as I can't locate one on eBay? 

 

The heat sink seems to be getting wet from fuel, I'm guessing there is a gasket issue /missing there?

 

Finally it came with a brand new reverse module and third servo,  unfortunately the box has been opened so I'm not sure if all is there and is it a simple job to fit with a 2channel radio? Can this be fitted to with of my nitro savages? 

 

Thanks.

 

 

 

[RCbutcher]

Isn't the 35 a 3.5 .21 engine? The .25 should be a little bigger. The .21 is the mk1 savage I think. What the spec differences are between the .21 and .25 bar engine is Idk.  

 

I think to use a reverse module you need a 3ch radio for the reverse servo. 

 

Mayb the new savage is a .25 but someone fitted the older 3.5 .21 engine. 

[gti power]

I don't know I thought a 25 was a 2.5 hp and the 35 a 3.5 hp but I really don't know. 

 

 

[Shudson]

RC Butcher is correct about the engine sizes - that is why your "3.5" is lower geared than your "25".

 

As far as reverse is concerned, you do really need a third channel. However, HPI did an electronic gadget to enable use of two channels (http://hpiracing.world/en/part/87039). Don't know if they ever did it separately, rather than packaged with a reverse conversion, but I seem to recall that it was quite dear. With current prices of cheaper radio gear, I suspect that it could probably be cheaper to buy a 3 channel set than to get the adaptor for your 2 channel.

 

You can download fitting instructions from HPI website.

[locky]

12 hours ago, gti power said:

Finally it came with a brand new reverse module and third servo,  unfortunately the box has been opened so I'm not sure if all is there and is it a simple job to fit with a 2channel radio? Can this be fitted to with of my nitro savages? 

 

You need 3 channel radio system (3rd channel must be switching type) if basic reverse 87032 module (no mixer) and it will fit any Savage. 

 

12 hours ago, gti power said:

The heat sink seems to be getting wet from fuel, I'm guessing there is a gasket issue /missing there?

 

Check glow plug is tight and glow plug washer condition. Check 4 cooling head bolts are tight.

 

12 hours ago, gti power said:

I decided to swap the engine over to my 35 and continue turning so I can also strip and clean the chassis on the 25.

My 35 has a 52 tooth spur gear,  I believe this will allow it to accelerate/wheelie quicker? Shall I order a 52 tooth for the 25 also (provided that it's a 25).

 

I run 47T spur with 17T clutch bell with a 25 or 4.6 engine. Yes 52/15 will give quicker acceleration but lower top speed. Wheelies depends on tyres/tuning/shock set up/surface grip. They are fun to start with then a pain if you cant control them, wheelie bar helps.

[Nitroholic]

You could buy the channel mixer seperate ...but to be honest ... I wouldn't bother. Best thing I did with mine was put it on E-Bay where it raised enough cash to buy a used set of extra thick IRC chassis plates. These lower the C of G slightly and make a big difference to handling.

 

I got nothing but hassle from reverse modules as the linkage had a habit of loosening off until the car dropped between gears. Often you will find the gears get wrecked when they don't change properly, or you change before the car has completely stopped. Had I left reverse...I can only think of one time I could have used it...when I buried the thing in a flower bed and could have backed out rather than having to go burrowing to find it.

 

If you plan on refitting the .21 engine ... then you would want the 52T spur. If you plan on going anything larger...then 47T will be what you want. 47/17 is pretty much optimal gearing, and #I run iot on my Savvy. It's a heavy lump of a truck, with a .32 motor, but that gearing allows for long controllable wheelies and enough top speed for fun.

 

There is no gasket between the cooling head and cylinder. You may have a shim in there to adjust compression. Properly and evenly torqued bolts are all it needs to seal, so check tham as Locky said.

[gti power]

OK thanks guys,  to be honest I'm not sure what to do now my 35 is a basher I bought it used and abused and I still continue to use it that way, where as the 25 seems to be much more looked after so I was going to make that the best it could be with what I have and perhaps sell it on with a Pontiac gto body I purchased and haven't even opened after seeing how the savage destroyed the one I had. 

I intend to refit the engines in there original chassis after tuning and cleaning has been done, am I wasting my time tuning the 25 engine if I'm going to transfer it into another chassis with different radio gear?

Thanks.

[gti power]

So can we just confirm the savage I purchased Saturday is actually better than my 35?

It's this one I have purchased http://hpiracing.world/en/kit/831 which I believe is the original Hpi savage? https://en.m.wikipedia.org/wiki/HPI_Savage

Also I was wrong the spur gear on the 21 was a 49Tooth.

[neil.b]

Its not a savage 35, there is no such thing. I suspect the savage you had before was a savage 21. 35 refers to the fact that the engine is a 3.5cc (cubic cm) or .21ci (cubic inch). The savage 25 is newer/better than a savage 21.

[locky]

No simple answer to your question which one is best.

 

You need to work out which engine runs best and has more life left, ie. how much pinch when warm.

 

You need to check the diff crown gear/pinion gear (43/13 oldest or 29/9 newest) and internals and diff shafts for wear, as well as wheel axles and drive shafts. Also all bearings for wear.

 

Check shocks are smooth and no bent shafts.

 

See what servos there are, check working and choose strongest for steering.

 

Then put the least worn parts on the chassis you want to keep.

 

[gti power]

1 hour ago, neil.b said:

ahh I see, well the savage I purchased Saturday is a 21 I have the box it came in but it does have 3.5 on the block.

I'll need to check but I'm certain mine has nothing on the block but I was sold it as a 35 off here.

[locky]

https://en.wikipedia.org/wiki/HPI_Savage

 

http://www.rc-trucks.org/hpi-savage-trucks.htm

[Nitroholic]

There is no Savage 35 ... but there was a Savage 3.5

 

Unless upgraded, the truck will not have the 29/9 tooth diff gears. You need to check what's inside the diffs as well. The earliest Savages only had a single cross shaft and 2 planetary gears. Later had 2 cross shafts.

 

The 'key' to a good Savage is to properly build a reliable set of diffs. My 'standard' recipe is to fit the 29/9 diff gears. These were brought in for the Flux models and are properly strong. Then add in a set of alloy diff cups:

 

http://www.ebay.co.uk/itm/HPI-86827-ALLOY-DIFF-CASE-SAVAGE-/221490349789?hash=item3391da86dd:g:8MYAAOxy3zNSlMfp

or the IRC ones....just as good.

 

Internals should be the latest version parts, or...if you can find them...the old Hot Bodies hardened ones, but these are hard to find.

 

You don't need titanium cross shafts....but you can fit them. You can also buy the later model diffs stripped from new trucks

 

http://www.ebay.co.uk/itm/HPI-Savage-X-4-6-29-Tooth-Diff-With-Alloy-Case-/351189401713?hash=item51c4850071:g:dOgAAOxyRhBS9hUZ

 

But be aware....you will need to upgrade your drive shafts to HD ones, get hte 9T pinions that go with them, and upgrade your axles too.

 

Brings your truck bang up to date, and makes yourt driveline as tough as it needs to be I run...on that setup...a twin engine Savage with a pair of .28 motors. I had to run a steel spur, locked slipper and flux single speed gearbox....as the power I was putting through the thing was causing 'issues' with the gear shift and was tearing up the slipper plates. Even with serious wide tyres, I had no diff issues ever.

[Burridge]

There is no Savage 35 ... but there was a Savage 3.5 [emoji4]

 

Unless upgraded, the truck will not have the 29/9 tooth diff gears. You need to check what's inside the diffs as well. The earliest Savages only had a single cross shaft and 2 planetary gears. Later had 2 cross shafts.

 

The 'key' to a good Savage is to properly build a reliable set of diffs. My 'standard' recipe is to fit the 29/9 diff gears. These were brought in for the Flux models and are properly strong. Then add in a set of alloy diff cups:

 

http://www.ebay.co.uk/itm/HPI-86827-ALLOY-DIFF-CASE-SAVAGE-/221490349789?hash=item3391da86dd:g:8MYAAOxy3zNSlMfp

or the IRC ones....just as good.

 

Internals should be the latest version parts, or...if you can find them...the old Hot Bodies hardened ones, but these are hard to find.

 

You don't need titanium cross shafts....but you can fit them. You can also buy the later model diffs stripped from new trucks

 

http://www.ebay.co.uk/itm/HPI-Savage-X-4-6-29-Tooth-Diff-With-Alloy-Case-/351189401713?hash=item51c4850071:g:dOgAAOxyRhBS9hUZ

 

But be aware....you will need to upgrade your drive shafts to HD ones, get hte 9T pinions that go with them, and upgrade your axles too.

 

Brings your truck bang up to date, and makes yourt driveline as tough as it needs to be [emoji4] I run...on that setup...a twin engine Savage with a pair of .28 motors. I had to run a steel spur, locked slipper and flux single speed gearbox....as the power I was putting through the thing was causing 'issues' with the gear shift and was tearing up the slipper plates. Even with serious wide tyres, I had no diff issues ever.

A twin .28 Savage?? [emoji15][emoji15] this I have to see!!!

[gti power]

One engine is bad enough to run let alone two?

[Burridge]

One engine is bad enough to run let alone two?

Agreed but I'm sure with all his know-how he makes light work of it

[gti power]

Need pics :-) 

[Nitroholic]

These are quite old pics...but all I had to change was the shocks. The Losi LSt ones were a bit soft, even with the heaviest springs. The rears are still Losi, but hte fronts are not MCD RaceRunner Evo 3 units. They are much better and reduce 'wallow' on turn in.

 

 

 

The inlet on the bonnet is a Kyosho Giga-Crusher filter unit....and Is the air inlet.

 

Have had some issue with breaking suspension arms, as it's a bit of a porker! So I keep it on the flat and just enjoy the noise.

 

Only bash it got filmed at:

pick it up from about the 5 minute mark

[SteveUK]

23 hours ago, Nitroholic said:

The 'key' to a good Savage is to properly build a reliable set of diffs. My 'standard' recipe is to fit the 29/9 diff gears. These were brought in for the Flux models and are properly strong. Then add in a set of alloy diff cups:

 

http://www.ebay.co.uk/itm/HPI-86827-ALLOY-DIFF-CASE-SAVAGE-/221490349789?hash=item3391da86dd:g:8MYAAOxy3zNSlMfp

or the IRC ones....just as good.

 

Internals should be the latest version parts, or...if you can find them...the old Hot Bodies hardened ones, but these are hard to find.

 

You don't need titanium cross shafts....but you can fit them. You can also buy the later model diffs stripped from new trucks

 

http://www.ebay.co.uk/itm/HPI-Savage-X-4-6-29-Tooth-Diff-With-Alloy-Case-/351189401713?hash=item51c4850071:g:dOgAAOxyRhBS9hUZ

 

But be aware....you will need to upgrade your drive shafts to HD ones, get hte 9T pinions that go with them, and upgrade your axles too.

 

Brings your truck bang up to date, and makes yourt driveline as tough as it needs to be I run...on that setup...a twin engine Savage with a pair of .28 motors. I had to run a steel spur, locked slipper and flux single speed gearbox....as the power I was putting through the thing was causing 'issues' with the gear shift and was tearing up the slipper plates. Even with serious wide tyres, I had no diff issues ever.

 

My savage still has the old 43/13, is the 29/9 defiantly worth it?

 

Just been looking at prices, whats the difference between these

http://www.modelsport.co.uk/hpi-sintered-bulletproof-diff-bevel-gear-29t-9t-set/rc-car-products/363706

and these

http://www.modelsport.co.uk/hpi-machined-bulletproof-diff-bevel-gear-29t-9t-set/rc-car-products/35325

 

Is it worth paying the extra? I already have IRC alloy diff cups.

[Nitroholic]

Depends what you want to do....

 

If you put a powerful motor in, the 43/13s don't last well. Drop in an LRP .32, and they will chew up. They are normally OK if properly shimmed...but it requires a fair bit of attention. If you fit a .25 or a modest .28 ...then you don't need the BP diffs. Still nice to have .. but not an essential.

 

I fit them for peace of mind.

[SteveUK]

It's currently running the MachStar 28 out of my converted hyper but I am planning on getting the LRP 32 when I have some spare cash.

 

What about the second question? Sintered or Machined?

 

Sorry for bombing the thread

[Nitroholic]

Then Yes....you want the uprated diffs.

 

I prefer machined to sintered.

[locky]

Sintered gears are holding up fine in my nitro Savages with various 28 engines, but it all depends on how you bash, jumps and landing on full throttle will damage most diffs. I've also run 43/13 gears for a long time without major problems.  Shimming helps reduce wear, as it reduces movement, dont forget the bevel gear. Also regularly check that the diff screws are tight, as this is a quick way to having a damaged crown gear. Machined gears are commonly used in brushless Savage Flux due to the much greater torque, as the machined is stronger than sintered, hence price difference. You can get a complete 29T sintered diffs from ebay jrc in USA for about £15 or less in auction and also 9T bevels.