Yama Buggy - Repairs, upgrades, mods and anything else

[dazzadazzadazzadazza]

Before everyone starts about the NON brand products, we all know that they are cheap, we all know they break, but everyone needs to start somewhere.

Starting with a Yama Buggy can only help appreciate the finer models later on

Ok, the point...

Here i am (and otheres) hoping to post details on every last part i have broken, modded and upgraded. Really do hope that I and otheres can help with questions and tips and debate the right mods to increase the fun factor.

Firstly Undo all metal screws and lock tight them with a medium grade. This is a must and will help not loosing all them tiny pieces. Do this before the 1st time out and save on the mission of trying to find bolts in the middle of a huge field (talking by experience of course)

Shocks, try not to over tighten the springs tension as the lower damper retainer will unthread. Half filling the shock with a 30 grade(depending on use) silicon oil will help with the sloppy bouncy nature of these.

Plastic idler gear carrier will soon burn out, i managed to obtain an FG metal part and fits great. Ebay has lots of these used parts floating about but check dimensions.

Tires, DO NOT THRASH ON GRAVEL STONE SURFACES! Sharp stones will shred these tires. All other HPI baja tires seem to fit the rims very well. And the FG wheels with glued tires fit the Hex/Square.

Engine compression, i have now removed the head gasket material and used head gasket sealant in order to increase compression. I'm left with .46mm clearance and the power is amazing! I do not suggest that anyone does this as i dont know for sure yet if the engine will granade or not but will post after another session.

Put an inline fuel filter on there, very cheap and easy.

Replace the horrid airfilter, it does not seal proper. grass sand and cows will get in there! Lots to choose from so worth having a little study on price V's quality.

Run on 25:1 fuel oil mix with the highest octane possible at your pump. Seems to be the safest all round mix.

Upgrade the exhaust if you have the cash. I have today picked up a new can and nearly have it installed. Not entirely sure what it has come off yet.(pics to follow)

Rear diff outputs have a weak point etched in there, these will bend untill they break. Will put the new ones through a forge hardening proccess in the near future and monitor the results. These are usually easy to remove once broken and should just fall out as not fixed in place.

Shell parts, removed as not needed.


I will update as more parts fall off

[beemer1664]

i just brought one mate, have shredded my rear tyre!
Whats the cheapest option to replace this!

Great little car for the money though!

Im also looking to upgrade the car slowly so any tips and info would be great mate, hopefully i can start returning the info!

dan

[dazzadazzadazzadazza]

This really depends on the surface you are driving on...
* fg marder/touring used wheel sets from eBay
* stock replacement from nitro tech
* dirt buster tires are very good but will cost more. These seem to be much tougher then stock.

[roofchopper]

hi got any pics, what a yama

[beemer1664]

its gonna be grass\mud possible gravel

ill have a shop around cheers mate

[dazzadazzadazzadazza]

A linky to what and where to buy. Been sat here for ages trying to get a picture to attach!!

AoWei 1/5th Scale Petrol Radio Control Yama Buggy 2.4Ghz (Model)

Hope this helps

[dazzadazzadazzadazza]

Originally Posted by beemer1664

i just brought one mate, have shredded my rear tyre!
Whats the cheapest option to replace this!

Great little car for the money though!

Im also looking to upgrade the car slowly so any tips and info would be great mate, hopefully i can start returning the info!

dan

These tires look ok but feel thin and less rubbery than the more expensive versions. Again, no thrashing about on gravel/stoney surfaces as they will shred

[beemer1664]

Still trying to find wheels, could you poss post a link to an ebay add for wheels and tyres that will fit please mate!

[Zakr]

this thread is so long im making a contents page.
hope it helps out people.
direct noobs here too.
im only ten pages in so far and im not including everything but if you feel it needs to be included i can add it in if you let me know.
will be doing this for a while.

subject---------------------------page------------post number

general usefull information---------1---------------1

tuning carb-----------------------1/5-------------12-13/86

thread lock rear left---------------1---------------17

link to mattys models--------------4---------------68-69

steering responsiveness-----------4/5-------------79-80.83

broken suspension arm tips--------6---------------107

broken suspension-----------------6/8-------------108-113/148 149

how to post pictures--------------6---------------120

info on chargers------------------10--------------194

[Zakr]

Oh and hey dazzadazzadazzadazza thanks for all the info you've posted.
And maybe this is just coincidence but a dazzadazzadazzadazza posted a coment on my YouTube video of my yama buggy the other day about tuning the "walbro carb" any chance it's you mate?

[dazzadazzadazzadazza]

If you was the guy racing around in the back yard then yep that was me : )

[Zakr]

i realy need help with tuning this carb.

of the two black needles the bottom one is low end right and top is high revs?
and whats the deal with the bigger silver screw it efects idle speed also.

anyway my car starts and idles absolutely fine
but unless i incredibly slowly pull the trigger it just bogs down worse than ever.

so do i have the correct idea of which needle is which? and should i be turning it in or out?
(im thinking in would make the car run leaner)

my basic settings were
top out 1.5 turns from tight in
bottom 1 turn out from tight in
maybe you can tell me what your settings are?

im annoyed that im having this much of a problem cuz ive owned a couple of nitros before now and never had this much greif from tuning

[dazzadazzadazzadazza]

I hear your pain. If you are having problems tuning the next thing to do is check the carb to engine manifold. Make sure there's no gap or signs of looseness. The carb might need to come off to verify this. Also check the fuel tank breather is letting in air correct.
Heigh is approx 1.5 turns out
Low is appeox 1.25 turns out
You are correct in thinking that needle going in shuts off fuel thus making leaner
To much fuel will also cause a bogging effect

Make sure you thread lock the screws you take out for inspection

[dazzadazzadazzadazza]

Fuel tank cap

This does seem to be poorly moulded and the tank becomes negatively pressurised.
Here is what I have done to resolve this:
Removed cap retainer which stops it moving too far from the tank. Under the cap there is a white plastic anti splash thingy(not required). Use a approx 2mm drill bit and re drill the top breather. Theres no harm in pushing right through to the rubber nipple and giving it a jiggle will verify this is clear.

[Zakr]

Well thanks I got it running pretty good and took it out it was great. Only after a while it gets moody again. And has no power or won't move.

While I was running it the rear wheel came off on its own twice.

Good in a way cuz It made me look under it and an engine mount screw was hanging on by it's last thread.

Then I took it out in the snow it slid 180 degrees and lightly tipped a wall with the rear right and broke its rear upper suspension arm.

I've already broken the right front upper arm before

it seams like the upper arms get all the stress or are quite weak.
Do you know any alloy parts that might replace them?

[dazzadazzadazzadazza]

I'm not sure what alloy parts will replace the arms. Would be a nice upgrade.
I have found that the camber adjusters on the arms pop out quite easy. Use PTFE tape to secure them. The tape is very cheap from any plumbers store.
Check your breather on the cap. Might be this that is causing a negative pressure in the tank.
After a full rebuild I had my Yama doing some good jumps yesterday. Got about an hour runtime out of it untill I lost a drive shaft.

[dazzadazzadazzadazza]

And regarding rear wheel. Rear left I believe. Thread lock it on as it will keep flying off.

[beemer1664]

good info, manages to get some marder wheels that fit woohoo, after taking it out lost front bottom arm screw(easily replaced!), the reciever switch has ceased through water ect (upgraded to waterprrof switch with cover) and also burnt another spark plug going to try the iradium tip plug any info on these guys???

Oh yeah pull start has ceased lol!

Iv just brought a team associated mgt 8.0 to play with whilst repairing this so all not too bad!

Thanks for setting up carb as been trying to source the info for ages now!

Cheers guys

[dazzadazzadazzadazza]

Lawn mower shops will likely have this size spark plug. I have not seen uridium plugs as of yet

[Zakr]

Yes it's rear left wheel
I'm gonna have to get some thread lock stuff

@beemer1664
That pull start would be easy enough to change. Or fix. I had mine off. a rock had got in there and taken off three of those "fins" in there.

I've taken a Stanley knife to the inside rim of the wheels where it would be inside the tyre just taken it down level with bolt holes. I felt it had a part to play in the tyres shredding. Let you know if it effects the tyres life.