RCU Forums

RCU Forums (https://www.rcuniverse.com/forum/)
-   RC 1/8th Scale Buggies (https://www.rcuniverse.com/forum/rc-1-8th-scale-buggies-244/)
-   -   RB S5 (https://www.rcuniverse.com/forum/rc-1-8th-scale-buggies-244/7939177-rb-s5.html)

joydude630 09-10-2008 03:20 AM

RB S5
 
Is the RB S5 good for a buggy or truggy?

Foxy 09-10-2008 04:02 AM

RE: RB S5
 
It'll be great for both. One of my favorite engines I ever had. Very strong on the bottom, runs cool as a cucumber, reasonable top end, lasts for gallons and gallons, easiest engine I ever broke in and tuned... Can't recommend it highly enough as a top sport/semi race engine. It'll give many race engines which cost twice as much a good run for their money.

joydude630 09-10-2008 04:32 AM

RE: RB S5
 
I plan to run the Nova standard plugs in it. Is it ok?

vladconnery 09-10-2008 05:53 AM

RE: RB S5
 


ORIGINAL: Foxy

It'll be great for both. One of my favorite engines I ever had. Very strong on the bottom, runs cool as a cucumber, reasonable top end, lasts for gallons and gallons, easiest engine I ever broke in and tuned... Can't recommend it highly enough as a top sport/semi race engine. It'll give many race engines which cost twice as much a good run for their money.
+1

Yes you can run nova plugs if RB plugs are not available in your area.

joydude630 09-10-2008 10:02 AM

RE: RB S5
 
I have never run a RB before. Is it a 2 or 3 speed needle?

Foxy 09-10-2008 10:05 AM

RE: RB S5
 
It only has (and only needs) 2 needles.

j_blaze 09-10-2008 06:08 PM

RE: RB S5
 


ORIGINAL: Foxy

It'll be great for both. One of my favorite engines I ever had. Very strong on the bottom, runs cool as a cucumber, reasonable top end, lasts for gallons and gallons, easiest engine I ever broke in and tuned... Can't recommend it highly enough as a top sport/semi race engine. It'll give many race engines which cost twice as much a good run for their money.
+1, rb's are pipe picky sometimes, mine likes the jp-4. good power and run time.

sh0wtime 09-10-2008 08:06 PM

RE: RB S5
 
i found i had to run mine really hot for it to make any power!
but it was a good engine that ran well & lasted OK ;)

rccheech 09-10-2008 10:45 PM

RE: RB S5
 


ORIGINAL: j_blaze



ORIGINAL: Foxy

It'll be great for both. One of my favorite engines I ever had. Very strong on the bottom, runs cool as a cucumber, reasonable top end, lasts for gallons and gallons, easiest engine I ever broke in and tuned... Can't recommend it highly enough as a top sport/semi race engine. It'll give many race engines which cost twice as much a good run for their money.
+1, rb's are pipe picky sometimes, mine likes the jp-4. good power and run time.
+2, RB's like the JP-4.

joydude630 09-10-2008 11:53 PM

RE: RB S5
 
I plan to run the OS 2060 for the time-being. I hope it holds a tune when I use the Nova standard plugs.

vladconnery 09-11-2008 07:02 AM

RE: RB S5
 


ORIGINAL: joydude630

I plan to run the OS 2060 for the time-being. I hope it holds a tune when I use the Nova standard plugs.
The plug does not have alot to do with it holding a tune other than good plug bad plug. Tune is mainly air + gas if you get that right whatever plug your running is already factored in. RB's are well known for holding a tune like a vise. Also they like it slightly rich on the lsn. tune lsn 1st then your hsn setting will be a breeze. I can call my temps with a simple turn of the hsn and generally be correct within 5-10 degrees. RB's take atleast a gallon for true breakin and to show you it's real power the one drawback of the rb. If you can call that a drawback however that also coincides with there long life. True break in is when the engine is up to temp remove the plug and turn the flywheel there should be little to no resistance at tdc. With plug in it should always be difficult to turn over thats called compression and thats a good thing.

My suggestion is to follow the rb breakin run it slightly rich for then entire gallon and always and I mean always have it up to temp atleast 220. Preheating the enging before starting is a + and generally necessary on the first few starts. Running an engine below temp less than 200 is as bad or worse than running it too hot. Cold engines actually generate more wear due to the nonexpanded sleeve rubbing against the piston. Correct operating temp causes sleeve to properly expand and allow the piston to move up down with minimal wear against sleeve. RB's perfomance range is 220 - 260 some run hotter I have always generated good to great power in this range. I generally run mine at 240 for just practicing and 250-260 for races. Keep in mind every engine even of the same type (S5) will be as different as a fingerprint. Some will like it hotter some will like it cooler no two engines are the same.

pete2222 09-11-2008 05:07 PM

RE: RB S5
 
I have one in my buggy. It is second hand, but I'm amazed at how good this engine is performing so far compared to my previous (HB .26). It starts so easily. Idles perfectly and is insanely powered for bashing. I don't know how good it would be in a truggy though, which is a lot heavier.

As for the comments on engine temps. I thought that engines run hot when there is more friction due to them running leaner with less oil passing through. I'm not convinced that running with a cool temp of say 190 F would cause excessive wear. If you run it in the freezing snow though that's a different story.:D

vladconnery 09-11-2008 08:43 PM

RE: RB S5
 


ORIGINAL: pete2222

I have one in my buggy. It is second hand, but I'm amazed at how good this engine is performing so far compared to my previous (HB .26). It starts so easily. Idles perfectly and is insanely powered for bashing. I don't know how good it would be in a truggy though, which is a lot heavier.

As for the comments on engine temps. I thought that engines run hot when there is more friction due to them running leaner with less oil passing through. I'm not convinced that running with a cool temp of say 190 F would cause excessive wear. If you run it in the freezing snow though that's a different story.:D
I am not going to rebut that comment. I will just highlight and let some other racers chime in on it. Somehow I doubt anyone would agree with you but sometimes its best to just sit back. Let others prove or disprove my comment on running your engine below temp.

youwish16 09-11-2008 09:01 PM

RE: RB S5
 
1 Attachment(s)
its not an s5 but its close! just got it today, havent even started it yet(have to add a shim). look how bald the tires are! lol


j_blaze 09-11-2008 10:10 PM

RE: RB S5
 
why do you "have" to add a shim? it should run fine as is, its an rb.

what_stanger 09-12-2008 12:56 AM

RE: RB S5
 
to run 30 percent you're supposed to add a shim.

I shimmed my WS7 and run 30, the way I see it is a shim is cheap as hell, especially compared to rebuilding the engine early. A well kept RB will last for many gallons.

joydude630 09-12-2008 01:03 AM

RE: RB S5
 
Thanks for the comment guys. I will make sure I will tune the LSN first and then HSN and follow the RB break in process. Cheers.

pete2222 09-12-2008 10:55 AM

RE: RB S5
 


ORIGINAL: vladconnery



ORIGINAL: pete2222

I have one in my buggy. It is second hand, but I'm amazed at how good this engine is performing so far compared to my previous (HB .26). It starts so easily. Idles perfectly and is insanely powered for bashing. I don't know how good it would be in a truggy though, which is a lot heavier.

As for the comments on engine temps. I thought that engines run hot when there is more friction due to them running leaner with less oil passing through. I'm not convinced that running with a cool temp of say 190 F would cause excessive wear. If you run it in the freezing snow though that's a different story.:D
I am not going to rebut that comment. I will just highlight and let some other racers chime in on it. Somehow I doubt anyone would agree with you but sometimes its best to just sit back. Let others prove or disprove my comment on running your engine below temp.
Can someone convince me then. Has a proper study or research article ever been published on this? I would like to see it. Isn't it the case that friction wears the engine out? Is there more of this at a higher temp (i.e. less oil lubricating a leaner engine and so more heat generated by friction) or is there less friction at the higher temp due to the piston liner expanding.

One thing I've found is that glow plugs seem to last much longer for me at lower temps (190F), which is adding up to a significant cost saving.

what_stanger 09-12-2008 11:32 AM

RE: RB S5
 
Pete if you have the power you want, and have the engine at a reliable tune......I wouldn't worry about it.

Generally speaking temping is just to be safe. I tune for performance and make sure i can see a thin line of smoke at WOT. I then run some laps hard and i'll check the temp just to be safe. Depending on the day and where you're running it can vary. My temps generally float around 220....but I've been as high as 240-250 on a hot day, still saw smoke and knew I wasn't lean.

running the engine at 190 vs 230 isn't going to make a difference as far as friction....at least I sure as hell wouldn't think so. It would be really had to test that. Once the pinch is going it REALLY wouldn't have an effect. Its not an extreme so it would be very hard to ever test such a theory.

EDIT: i meant once the pinch is GONE it wouldn't have an effect.

vladconnery 09-12-2008 08:08 PM

RE: RB S5
 
Ok,

Let me chime in so you understand what I'm telling you. Running your engine at temps above 200 is a must why? When your engine is at temp the the sleeve expands to allow the piston to move freely through the stroke. With minimum resistance causing less sleeve wear while keeping maximum compression. When the engine is running below temps of 200 the sleeve has not expanded. The sleeve is now pinching the the piston through the entire stroke and even more at tdc. hence a new engine often gets stuck at tdc. you know why it stops getting stuck because yo have worn the tdc pinch down. Which is going to happen anyway. Your just making it happen prematurely and at cold temps its wearing more than it should. Continued running at low temps will eventually wear the sleeve prematurely making for an early grave. Why do you think everyone tells you when your breaking your engine in get it up to temp quickly. Preheat your engine before starting when breaking your engine in.

1. so the piston won't get stuck at tdc from a cold sleeve that has not expanded.
2. so you don't wear your pinch prematurely and or more than it will wear through normal use.
3. so the engine is easier to turn over the piston and sleeve are not tight placing unwanted stress on your conrod
3. So your engine life is as long as it can be.

cold engine that is difficult to turn over with plug out thats called pinch
cold engine thats is easy to turn over with plug out thats called a paperweight

warm engine thats difficult to turn over with plug in thats called compression
warm engine that has slight resistance with plug out thats called broken in

Perfect example of a engine that has died from sleeve wear. Engine runs great and has power until it reaches temp then it cuts out. Due to the sleeve has expanded properly and there is no pinch left to hold compression. ie. sleeve is worn either through running at low temps or has had a long life and it's time to kick the bucket.

Hey you don't have to take it from me run all your engines at 180 from breakin to death. The only thing I can tell you is the period between breakin to death will be short like leprechauns. I wonder why all those guys run around with rolls of aluminum foil rapping there heads to get temps up quickly they are so silly.:eek: Silly NASCAR dudes with there cute little engine warmer blankets on the car before the race. Silly car manufactors reminding us that cold starts cause the majority of engine wear. All these silly people doing silly things to warm there engines. Silly plinking noise your engine makes as it cools back down i.e. unexpanding. The world is filledd with such silly people that do such silly things[:o].

sh0wtime 09-13-2008 02:41 AM

RE: RB S5
 
TRUE DAT


you need to run an engine at the correct temp to be using the correct operating clearances
too hot or too cold & you're reducing the lifespan through premature wear :eek:

people have learned this through experience & they're trying to help you learn the lesson the easy way (ie without paying for an engine everytime you get it wrong!)

its up to you

you can take a horse to water but you can't make it drink :eek:

whichever way you go, have fun :D

what_stanger 09-13-2008 01:54 PM

RE: RB S5
 
Full scale engines are a little bit different. For one they don't have a 'pinch' as everyone calls it. They have rings to seal the cylinder.
Yes its true cold starts wear engines the most, but thats because all the oil has sat in the oil pan all night and none is at the top of the engine.

I was assuming his engine was already broken in. If thats the case 190 dergrees is not going to shorten the life of the engine.




ORIGINAL: vladconnery

Ok,

Let me chime in so you understand what I'm telling you. Running your engine at temps above 200 is a must why? When your engine is at temp the the sleeve expands to allow the piston to move freely through the stroke. With minimum resistance causing less sleeve wear while keeping maximum compression. When the engine is running below temps of 200 the sleeve has not expanded. The sleeve is now pinching the the piston through the entire stroke and even more at tdc. hence a new engine often gets stuck at tdc. you know why it stops getting stuck because yo have worn the tdc pinch down. Which is going to happen anyway. Your just making it happen prematurely and at cold temps its wearing more than it should. Continued running at low temps will eventually wear the sleeve prematurely making for an early grave. Why do you think everyone tells you when your breaking your engine in get it up to temp quickly. Preheat your engine before starting when breaking your engine in.

1. so the piston won't get stuck at tdc from a cold sleeve that has not expanded.
2. so you don't wear your pinch prematurely and or more than it will wear through normal use.
3. so the engine is easier to turn over the piston and sleeve are not tight placing unwanted stress on your conrod
3. So your engine life is as long as it can be.

cold engine that is difficult to turn over with plug out thats called pinch
cold engine thats is easy to turn over with plug out thats called a paperweight

warm engine thats difficult to turn over with plug in thats called compression
warm engine that has slight resistance with plug out thats called broken in

Perfect example of a engine that has died from sleeve wear. Engine runs great and has power until it reaches temp then it cuts out. Due to the sleeve has expanded properly and there is no pinch left to hold compression. ie. sleeve is worn either through running at low temps or has had a long life and it's time to kick the bucket.

Hey you don't have to take it from me run all your engines at 180 from breakin to death. The only thing I can tell you is the period between breakin to death will be short like leprechauns. I wonder why all those guys run around with rolls of aluminum foil rapping there heads to get temps up quickly they are so silly.:eek: Silly NASCAR dudes with there cute little engine warmer blankets on the car before the race. Silly car manufactors reminding us that cold starts cause the majority of engine wear. All these silly people doing silly things to warm there engines. Silly plinking noise your engine makes as it cools back down i.e. unexpanding. The world is filledd with such silly people that do such silly things[:o].

pete2222 09-13-2008 03:15 PM

RE: RB S5
 
Hey Vladconnery, since you're so sure in your knowlege of this subject, can you explain why leaning an engine out makes it hotter. Is it because there is less oil lubricating the piston/liner and so more heat genrated by friction perhaps?

sh0wtime 09-13-2008 03:45 PM

RE: RB S5
 
just to chime in here, its simple physics & generally accepted fact that 2 stroke engines run hotter with a lean mixture, thats everything from an RC car to a Motocross bike!


got you a link to an online guide to tuning that might help answer a couple of questions you might have
its not in my words but on a quick look through it appears to be mainly sound advice ;)

take a peep [link=http://www.*********.org/cars_eng-tuning.htm]HERE[/link]

pete2222 09-13-2008 04:05 PM

RE: RB S5
 


ORIGINAL: sh0wtime

just to chime in here, its simple physics & generally accepted fact that 2 stroke engines run hotter with a lean mixture, thats everything from an RC car to a Motocross bike!


got you a link to an online guide to tuning that might help answer a couple of questions you might have
its not in my words but on a quick look through it appears to be mainly sound advice ;)

take a peep [link=http://www.*********.org/cars_eng-tuning.htm]HERE[/link]
That's a useful guide thanks, but it doesn't actually explain the reason why leaning an engine makes it run hotter nor does your simple physics comment. Is it becase there is more heat genrated just because there is are more engine revs and so more combustion cycles or is there also more heat from friction due to less oil and poorer lubriation ?


All times are GMT -8. The time now is 11:32 PM.


Copyright © 2026 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.