30 degree north 29cc bws racing olimat silenced pipe

[romper4444]

Hey there just wanted to inform everyone of my experience with the bws racing 29cc engine that came in my 30 dnt truck (losi 5t clone) , truck itself has been awesome, bought the roller from KM/Rovan site. No issues there except he sent the wrong servos, but helped me figure it out(servo dimensions matter in these trucks)
I'm guessing I got about 5 tanks of gas if that thru the motor before it lost Compression. It's down to about 50psi. Started getting hard to start, wouldn't idle well. Haven't pulled it apart yet to see what actually happened if anything. Engine did have great power while it ran. Motor had 1 tank of break in, was tuned perfectly(I'm a Mechanic) ran an Olimat silenced pipe, which to my surprise actually made less power than the included 30 deg North unsilenced pipe. That pipe was just way to loud so I went with the olimat, which was nice and quiet, but I figured for $400 I'd at least maintain the same power and be quieter. No such luck, So I don't recommend that pipe unless your only concerned about being quiet. I also tried the bolt on rovan silencer on stock pipe and it hardly made a difference if anyone was looking to try one(they also scrape the ground on full suspension compression)
Any advice on what motor under $300 to try next? I'm thinking the zenoah g320 is prolly my best bet, but I'd kinda like to try the 30.5 or 32cc rovan engine and experiment with some porting myself to see what I can get out of it. I would like more rpm and the ability to pull a 20t pinion as I find the truck is too slow(19t is stock)
Any and all input welcome.

 

[Rep732]

So a few things I see, no engine will survive in the conditions you put that truck through especially with that air filter. Yes it's rc and it's fun but there is a line where the conditions are just a death sentence to these rigs. I'd bet all of bearings would need to be changed at this point and all of the hinge pin areas are severely worn.

Clone engines don't really last too long and they come with a plague of various running issues and it's not one thing in particular. From what I've seen here the problems are all random and may or may not show themselves to you.

Before you buy an engine take it apart and take pics of the cylinder, piston and the intake side of the carb as im pretty sure you sucked in dirt and what did your engine in.

 

[romper4444]

I appreciate the observations but the pics are directly after the last run, so of course the air filter has dust on it, as does the whole truck. Everything is tight as a whistle still, I like to use dry graphite lube on links and joints to keep wear down and no dirt or dust adhesion to the various components. I pulled motor apart, zero dirt inside, nothing inside the intake tract from the carb inlet on thru to motor. It appears what caused loss of compression was the sharp edges and burrs along exh port with the main issue being a sharp piece sticking out off transfer port divider creating a gouge along piston skirt up into ring
I ran the motor as it came outta the box always knowing in the back of my mind it could be roughly the 1 or 2 in 10 of these motors that have defects inside. Some run great for a long time and many run just "good" for an acceptable amount of time. Some fail quickly.
I was thinking originally, should I tear this motor down and inspect before break-in. Preemptive maintenance to avoid early failure?
Nahhhh lol, let's run er. if it fails I'm eager to upgrade for more power anyway. I googled rebuild kits and they are like not even 20 bucks for the cheapies! and 50 to 100 for a big bore rebuild depending on cheap or a ddm esp kit or something.
Just so you know my background I've been a licenced mechanic for over 20yrs and an avid powersports hobbyist, RC nut my whole life so I am fully aware of the knowledge required to maintain and rebuild any kind of engine, what causes failures, etc etc etc.
I'll post pics of the internals, I just was one of the unlucky ones that got a not so good engine from the factory.
What id really like input on is thoughts or personal experiences on big bore top end kits, pre ported cylinders, are they worth it power wise Vs stock cheapie rebuild and port it myself Vs stroker crank install Vs a stock zenoah g320 bolt in and go type thing? Really I'd love to try every option and compare as tinkering is my passion and 5th scales are newish to me so it's something fun and inexpensive to tinker with. The last avenue of RC I haven't explored until now! (Well there's nitro helis but I won't go there lol)
Any input or experiences i much appreciate.
I love to learn about what others have learned on their mod path. Sorry for the novel here, I'm terrible for that lol

 

[romper4444]

Kinda disappointed, expected more action on this forum

 

[Rep732]

I run nothing but the olimat pipes both silenced as you have and unsilenced and their great so I disagree on your opinion.

Here since your telling me it's just "dust" on your rig. Let me show you what fresh off the table built g340rc engine looks like 10 minutes into running with dust. I'm a mechanic too but sometimes I do dumb things and this was one as it cost me about 300 to fix not to mentionall of the bearings i had to replace because of the dust. don't know what else to say or show you other than been there done that and i told you my advise.

 

[spents]

Kinda disappointed, expected more action on this forum

there usually is more action here fella, its just been a tad quiet of late ,
post up some pics of any problems you're having cos thats the best way to get replies, if we can see pics we can offer advice much more easily ,
and may spot something you didnt spot yourself,
these engines will suck dirt at some point in very dusty conditions,
also check the carbs insulator block, the clone engines usually aint the best, and a loose carb can create a point between the carb and insulator or insulator and engine where dirt can be sucked in, that would also make for poor starting as well,

 

[3illmesmart]

I put an ESP ported top end on my engine and am very pleased.

 

[Rodknee]

to suggest olimat pipes don't work is a 1st. well regarded pipes in the industry
might be an issue with your setup mate