Hey

I got a STS .28 there with my SS, Ive had the 21 and i currently have S-25 in my other savage, so ive got a idea what im doing when breaking in a engine, im no expert or i wouldnt be askign for help. But i started up the sts and thats no problem. I have the throttle completely closed expect for the millimeter so that it can idle. Once it idle's for a couple of seconds it starts to rev up. I tought it just revving up for a sec, until i heard it change gear and carryed on revving. Ive stopped the engine and started it up 3 times again and it does the same thing. I dont want to start it up again and leave it as i dont want to ruin this engine. Can nebody please give me some idea why it is doing this. Ive never had this problem befre on breaking ina a engine. Im gathering it has a air leak somewhere becuase it must be getting the air somewhere for it to be doing this.

It seems the fuel supply is not enough when idling. Check those parts;
1)the low speed needle too lean?
2)the back pressure of tuned pipe is not enough?
3)manifold gasket broken?
4)fuel tank's cap leaking?
5)back pressure line or fuel line broken?

Could u tell me what the setting is for LSN for the STS .28 as i received no manual only th box and the engine. Ive done everthing thats list , i change the fuel line, change the fuel tank. The gasket is brand new with the engine so it can be that. I have the hpi ribbed tuned pipe on it so im not to sure if that give a lot of back pressure. It still is revving high and im starting to lose confidence with this engine.

Let me know the carb setting of your engine. How much turns out of each needle?

There is a running setting of mine. not break-in setting. If your engine still new,you need to rich the main needle.

High speed needle -- about 2 ~ 1-1/2 turns out
Low speed needle -- about 4 turns out
I'm using 0.4mm shims with 25% nitro,#5 plug.

well the LSN is at about 4 and half turns but i stuck it at 5 turns out. Not too sure about the HSN. Yes the engine is brand new. just wondering what are shims? never heard of that term?

4~5 turns out should be ok. Check the back pressure. It must be something wrong. fuel tank? tank's cap? presure line? tuned pipe? gasket? Or you lean the HSN too much?

This engine comes with many shims. After break-in you need to take out some shims. 25%+ 0.4mm;20%- 0.3mm.

Regards,
Dino

ive done everything same problem:

-Ive change the tuned pipe,
-Ive changed the fuel lines and pressure lines
-Ive replaced the gasket
-Ive set LSN
-Ive change the fuel tank

Ive done every single thing, i must say at this rate there is something wrong with this engine. Ill wait your post dino before i decided to return it. Ive never seen an engine revving so high with a near enough closed carb!

Pttf,
Please let me know the total length of your pressure lines.
Have you try to rich the low end more?
Can you take a photo of your engine and tuned pipe mounting on your car?

here is my engine

http://www.ni-r.com/STS.28.JPG

Please see the attachemet;
1.The fuel tube is not safe for non-blocking of fuel. I suggest you to turn the direction of Intake fuel pipe and go the green line way.

2.It seems the fuel tank already broken. This will make the engine lean. Fully clean its outside. Then start your engine and check if it still oily outside.

3.Try to make the throttle linkage and servo arm vertical. Then make sure it will back to the idle place everytime when you close the TX throttle. Why you don't have return spring? Or I can't see it?

Hope this help...take another photo for me. I want to see the whole throttle linkage system.

just asking.....
 

hi there, i just want to ask if the STS .28 is directly fit to savage engine mount? if not what engine mount should i use?
i'm new in this field...
thanks in advance...
:confused: :confused: :confused:

I just got my Sts .28 and I got the gpm mount with it, The person at the R/C mall in Hong King said I needed it, well if you run a 19 tooth CB and a 49 tooth spur, with the hot bodies side plates, and original ,(but if you run a 18 tooth CB or smaller it'll be fine)you will need to dremel a spot on the plate so the engine can move to the side more and foward! Engine so far ran great! Installed it and primed it 1 pull with my finger over the exhause , and it fired up on 1 pull.. My big problem right now is, I have the Ofna aluminum 3 shoe clutch, and it seems to slip a lot, anyone have a better clutch shoe set up?

Ok i done everything u said, in the picture.

Still revving up. The fuel tank was'nt broken, it just was'nt sitting right on the holder and thats the fuel tank from my other savage which work's perfect. The throttle linkage is like that to make sure the carb is at mm open, and plus iw as changeing a servo at the time and their is a throttle return spring. I really have not got a clue whats going on here. I'm not gonna let it rev out of control as that will ruin the engine.

could u give us the break in setting of the LSN?

Hey pttf

when I got my sts .28 I started it for the first time, at factory settings,

ls = 4.5 turns out

Hs 3 turns out

and it raced like your did, I just closed the throttle more with the idle screw, to almost closed. like maybe a red Pube hair? :) and it idled perfect! Just my 2 cents!

oops....yes....skybolt58 is right. Maybe it is just the sample answer. Thank you skybolt58.

Pttf,please close the throttle more with the idle screw(counterclockwise). Till the engine almost flame out then screw it a little.

Here is the new 21/28 manual. Maybe someone need it.
http://www.stsrc.com.tw/info/21%2028...ual%20v3.1.pdf

oops.. should post here...

heard there will be rotor plate avaliable for STS.28.. when will that be?

regards..

should be May.

thanks again, dino... 谢谢！

I need a roto start :( I have blisters between my fingers!) lets get one made! we need it, we are all spoiled! :) :) ;)

cheers lads, i will give that a go tomorrow

OH yes, Bad news, I got this sts 28 to hopefully beat my sons Losi LST.. Not happenning ! I ran a gallon on break in, took the 3 .01 mm shims out, put in a new #5 OS plug, ( I run 20 % nitro 12 % oil) and a 19 tooth CB and a 49 tooth Spur, and My son's Losi LST still flew by my savage like as mine was a Traxxas ELECTRIC STAMPEED, How sad, a savage cant beat a losi! :( ;( I guess I wil be selling my savage and get me a stock losi, 55mph out of the box! we had it clocked about a hour ago...

Or.. get a 3Speed savage conversion :smile:

i have to say here, now thats a BS. Have u ever thought of tuning it right? My savage with stock S25 engine can beat a GS S.U.T. [which is a truggy] and u meant the SAVAGE WITH STS .28 cant beat the losi stock :confused: :rolleyes: :rolleyes:

forgive me...i hope u just kidding.:)

:smile: :smile: you're sold on that STS .28 which is not a bad thing :)

Sorry ! But I wish I was kidding, I have been running Glow engines since 1973, I am sure I know how to tune a engine, cars/trucks/planes/boats/and helichopters. I have a lot of money in this savage! I doubt very much that the 3 speed would work, it needs more than 10% more speed to get past that losi lst. I thought for sure once I put that sts .28 in. and when I broke it all in I thought it was faster, But well it was faster than the stock .25! a lot of snott, But not enough for the losi lst. gearing is the main issue! the lst has a higher 2 speed ratio, and the diff's are higher geard. so I plan on buying a lst, and put my sts.28 on that.. then I can beat my son! thats the only way! on the lost ratio: is CB low 18 tooth, high 25 tooth, and the spur is 70t low and 63t high.. now that is some ratio's

1/8 buggies are designed to go around monster trucks :) Less weight and lower center of gravity woohoo

If your talking about a losi lst, well that is a 1/10 scale Monster Truck. but it is bigger than a stock savage

Nah, I was talking about a LOSI LST killing machine :)

A friend is going to power his buggy with a STS .28 :D I have a STS .21 in my buggy but being slack as I am break-in is not yet fully complete. (Currently working on building a brushless 1/18 stadium truck)

OK here is a good question for the sts .28 in a savage.. What would be the best (fast at high end) cb and spur) that won't strip out.. I had a titanium 49 tooth spur, wit ha 19 tooth CB and the CB wore out in 3 tanks after break in! so sau after 8 tanks. cb was shot! and it was a gpm cb..

Heres my vid of the STS in my ofna buggy on around Tank 7. I'd just leaned it out, and wasn't fully tuned, i also lost radio contact not long after (Receiver batt) lol.

http://www.rcpics.net/view_single.php?medid=51039

Gee , watching that video made me go out and fire up my snowmobiles, seing that snow! AHHHHHhhhhh the smell of 2 stroks.. that buggy looks to go good. I have a Hyper 7 PCR pbs andwith the hyper 21 it was just a hair slower than my sons losi lst.. this is wht I plan on selling the slow savage and get a lst and put my .28 sts in my hyper 7.. it aught to be fast!

Yeah, it goes pretty good, i have it dialed in just right now, it just seems to get better and better, i'm gonna stick it in one of my savvys at some point and see how it goes in there :D

Hi dino.tw!!!

I just got and installed my STS28 yesterday.

I just have two concerns....

1. When I was configuring the radio, There are times when the carb gets stuck when im attempting to go WOT. What i usually do is 'double clutch' the throttle, which seems to 'unstuck' whatever is blocking the slide.

2. On the CG image of the shaft starter, i noticed that the hole for the rotostart is at the side. Will this fit the savage? I mean, the savage's rotostart hole is on the upper left corner. I hope you could accomodate us Savage owners :D


Right now im pumping some iron and strengthening my pullstart arm as im about to break in the beast! haha!
:D

ok i think i found the problem. I noticed when the engine is running there are bubbles in the fuel line which are not moving. So i gather there is lack of compression somewhere. So this should narrow the problem which is causing the engine to run high. Any suggestion's

That could also be a sign of BOTH the LS too lean and also the HIGH end.. Mine is all broken in, the LS is like 6 turns out, perfect responce! the HS is 3 turns out, and it is getting 37000 rpm. probably needs more time to get the 40000 rpm.. Rule of thumb! rich is Nice Lean is poor! best to run it rich than lean. it it sounds like lean is your problem.. What percent oil/nitro fuel you using? I was using 20% nitro and 12% oil. engine seemed to like it! ALSO! did you take the baffle out of your pipe? if so? put it back in for the back pressure and also pressure for fuel tank.

Re: just asking.....
 

Yup. direct fit/

I would suggest swapping your titanium spur with a good delrin one.

I can't help but comment here. LST powered by a mach .26 is a fairly rapid machine, there's no doubt. But on a track the high gearing doesn't usually equal a decent lap time - far from it with a big heavy machine like either the LST or Savage. I suppose it depends on what your priorities are.

For top speed, it's a merely a question of BHP, Power to weight and gearing. 55mph? I doubt it - how did you get this reading?