R/C Tech Forums

Go Back   R/C Tech Forums > General Forums > Nitro Off-Road

Reply
 
Thread Tools Search this Thread
Old 10-16-2009, 02:04 PM   #46
Tech Regular
 
NJA82's Avatar
 
Join Date: Apr 2007
Location: Cairns, QLD
Posts: 430
Trader Rating: 33 (100%+)
Send a message via MSN to NJA82
Default

Anyone know where you can buy a new OS 26 4 stroke like you guys are using in your converted GT2`s? Have searched around but no success....
NJA82 is offline   Reply With Quote
Old 10-19-2009, 02:48 PM   #47
Tech Fanatic
 
SteveP's Avatar
 
Join Date: Mar 2002
Location: So Cal
Posts: 918
Default

I don't believe they are making these engines anymore, or at least they're not importing them. You can try ebay.
SteveP is offline   Reply With Quote
Old 06-06-2010, 11:36 AM   #48
Tech Rookie
 
Join Date: May 2010
Posts: 12
Default

Quote:
Originally Posted by NJA82 View Post
Anyone know where you can buy a new OS 26 4 stroke like you guys are using in your converted GT2`s? Have searched around but no success....
You can find them on ebay from time to time. They'll range from $150 to $300 for a nib. Be sure to get the car version instead of trying to adapt an airplane version. They are completly different animals. Larger valves, different cam, and crank. The car version runs at much higher rpms. Os made two different displacements. The FS-26SC and the FS-40SC in both bump and pull start. Parts like cylinder sleeves and pistons are about half the price of good two strokes. You can also look for the kyosho superten. That's how I got my first engine. Bought a ragged superten with a great engine for a great price. There aren't a whole lot of supertens that have the four strokes but it's something else to look for. Good luck.
dcap is offline   Reply With Quote
Old 06-06-2010, 12:14 PM   #49
Tech Regular
 
freestylinmotox's Avatar
 
Join Date: Apr 2009
Posts: 364
Trader Rating: 7 (100%+)
Default

Here is Damon's website.

Click on products for info on how to purchase a kit!

http://www.thumprc.com/
__________________
when in doubt, throttle out! braaap!
freestylinmotox is offline   Reply With Quote
Old 06-06-2010, 01:04 PM   #50
Tech Adept
 
Join Date: Jul 2009
Location: Florida
Posts: 120
Trader Rating: 3 (100%+)
Default

Well here goes, this is a video of my Losi 8t setup with a .52 four stroke.
Gearing in the video is 15/48 majorly under geared, run 18/45 now and its still not right. Ill get some track video up here soon.

OK, i just found out i can't post links yet? Anyways go to Youtube search,

Losi 4 stroke

Its named "4 stroke powered losi 8t truggy"
speedworks is offline   Reply With Quote
Old 06-06-2010, 02:18 PM   #51
Tech Addict
 
Join Date: Mar 2010
Location: Connecticut
Posts: 711
Trader Rating: 14 (100%+)
Default

There is still 1 very important thing you guys forgot to mention about 4 stroke/rotary engines. Something that has the potential to double the power, but not applicable to 2 strokes, at least not in rc.
DuckStang is offline   Reply With Quote
Old 06-06-2010, 02:47 PM   #52
Tech Fanatic
 
ses601's Avatar
 
Join Date: Sep 2009
Location: south jersey
Posts: 801
Trader Rating: 29 (100%+)
Default

Quote:
Originally Posted by NJA82 View Post
Although i will agree with you that the "current" 4 stroke 450cc moto`s are superior in power to the older gen 250 2 strokes, i have to say that the reason you dont see them anymore on the track is emission laws, they outlawed 2 strokes for racing a few years back hence why every manafacturer jumped into 4 strokes.

The very first production 450`s werent as powerful as they are now and a well setup 250 2 stroke was still a faster, lighter and more nimble bike for racing, 4 strokes make it easier for the novice rider to go fast, making the sport more freindly for new comers, 2 strokes are an experts engine when you start making big power because the powerband tends to be narrower. But they are a lot cheaper to rebuild, have a lot less moving parts and weigh a lot less, the current 450 bikes are a bit over 100kg, whereas the factory 250`s of the late 90`s and early 00`s were more around the 90-95kg mark, thats a big difference in the air and under braking etc.

All these comparisons work hand in hand with R/C, the motocross industry were forced into engine changes from laws getting tougher, our industry hasnt got these laws and the cheap, light, simple nature of a 2 stroke IMO will be the reason we will stay that way for a few years to come, unless something comes along that forces change... although fuel and emissions arent a problem with alcohol fueled engines.
just to clear a couple things up: sure, the government was going to get its way with the emission laws....however, yamaha jumped the gun waaaay early with their 400. these early big bore 4 strokes (specifically 426) were VIOLENT with power. they only continue to smooth them out year after year.

as for the weight, you don't even notice it. the reference to braking isn't really applicable since the engine-brake of the 4 strokes is so crazy. as you go through acceleration bumps, the bikes track so much better too, which makes them feel 10x lighter (you don't have the bike swapping all around under you). also, they are much easier to jump.


Quote:
Originally Posted by Davidka View Post
A current 250cc 4 stroke would eat a 2 stroke 250 on the track, not with peak hp, with drievability (though I imagine at this point they're pretty close in HP). 4-strokes were first driven into motocross by the manufacturer
exactly

in RC, it's awesome to watch a little 4 stroke rip around. however, for all those ex mx-ers at the track, nothing beats the current sound of 1/8s racing. the sound is as close as you can get to the old mx days
__________________
TLR SCTE 2.0
ses601 is offline   Reply With Quote
Old 06-06-2010, 03:00 PM   #53
Tech Champion
 
Roelof's Avatar
 
Join Date: Aug 2007
Location: Holland
Posts: 5,983
Send a message via ICQ to Roelof
Default

Somewhere in the old EFRA ruling for 1/8 onroad cars there is a limit for .21 2-stroke (still a standard rule) and .40 for 4-stroke, I think the FS40 would be the better choice but the .26 has a better (almost direct) fit.

I did do a search on the web and found on youtube also some movies about tuning these engines giving more torque and RPM.
__________________
Speed is only fiction but a 130+km/h MRS4 is for real.
Roelof is offline   Reply With Quote
Old 06-06-2010, 03:20 PM   #54
Tech Elite
 
Zerodefect's Avatar
 
Join Date: Apr 2008
Location: Underground, Ohio
Posts: 4,305
Default

.26 wouldn't do the trick in 1/8th scale. Wouldn't even stand a chance.

.54 would be the way to go. The better Saito mills are smaller than you'd think and really light. Besides, my car feels way better as a heavy Electric thn it did as a light nitro.

A conversion would need a complete chassis, motor mounts, possibly center CVD's if they move the center diff, flex tube to connect the muffler, giant clutch bell pinion gear, heavy flywheel, and an extra large cooling head.

Sounds like something BCE or Techno could pull off. Surprized none of the big RC companies have jumped on this.

The sound, idle, reliability, and fuel economy can't be beat. All my nitro airplanes have been 4 strokes, even my trainers. My bigger planes are gasoline.
Zerodefect is offline   Reply With Quote
Old 06-06-2010, 03:37 PM   #55
Tech Initiate
 
Join Date: Jun 2009
Location: Cleveand Ohio
Posts: 22
Send a message via ICQ to demonkevy666 Send a message via AIM to demonkevy666 Send a message via MSN to demonkevy666 Send a message via Yahoo to demonkevy666
Default

Quote:
Originally Posted by Zerodefect View Post
.26 wouldn't do the trick in 1/8th scale. Wouldn't even stand a chance.

.54 would be the way to go. The better Saito mills are smaller than you'd think and really light. Besides, my car feels way better as a heavy Electric thn it did as a light nitro.

A conversion would need a complete chassis, motor mounts, possibly center CVD's if they move the center diff, flex tube to connect the muffler, giant clutch bell pinion gear, heavy flywheel, and an extra large cooling head.

Sounds like something BCE or Techno could pull off. Surprized none of the big RC companies have jumped on this.

The sound, idle, reliability, and fuel economy can't be beat. All my nitro airplanes have been 4 strokes, even my trainers. My bigger planes are gasoline.
Associated AE 8.0 Engine is a .50 the steel fly wheel for that should work fine for a 4 stroke in that range.

I think gearing is the biggest problem as everything is made for a high rpm two stroke.
demonkevy666 is offline   Reply With Quote
Old 06-06-2010, 03:51 PM   #56
Tech Elite
 
Zerodefect's Avatar
 
Join Date: Apr 2008
Location: Underground, Ohio
Posts: 4,305
Default

I agree. Going to need a small, allmost as small as the center diff case size, ring gear on the center diff.

Otherwise the pinion would be so big it would move the engine too far out.
Zerodefect is offline   Reply With Quote
Old 06-06-2010, 03:59 PM   #57
Tech Initiate
 
Join Date: Jun 2009
Location: Cleveand Ohio
Posts: 22
Send a message via ICQ to demonkevy666 Send a message via AIM to demonkevy666 Send a message via MSN to demonkevy666 Send a message via Yahoo to demonkevy666
Default

Quote:
Originally Posted by Zerodefect View Post
I agree. Going to need a small, allmost as small as the center diff case size, ring gear on the center diff.

Otherwise the pinion would be so big it would move the engine too far out.
need a clutch bell that is just like the the pinion gear mounts of brush-less electric

the nitro clutch bells pinion's don't go high enough in teeth.
some spur gear do go plenty low enough though.
demonkevy666 is offline   Reply With Quote
Old 06-06-2010, 04:29 PM   #58
Tech Adept
 
Join Date: Jul 2009
Location: Florida
Posts: 120
Trader Rating: 3 (100%+)
Default

Quote:
Originally Posted by DuckStang View Post
There is still 1 very important thing you guys forgot to mention about 4 stroke/rotary engines. Something that has the potential to double the power, but not applicable to 2 strokes, at least not in rc.
Supercharger, Turbo, Nitrous?? Iv thought about all of them, they would add unwanted weight to the car/truck though. My 8t is already to heavy with the .52 4 stroke conversion... Added 4 stroke motor weight, fuel pump, fan setup, big steel flywheel, motor mounts and bigger clutching.
speedworks is offline   Reply With Quote
Old 06-06-2010, 04:35 PM   #59
Tech Adept
 
Join Date: Jul 2009
Location: Florida
Posts: 120
Trader Rating: 3 (100%+)
Default

Search Losi 4 stroke on youtube i have 2 videos of my truck on there.
speedworks is offline   Reply With Quote
Old 06-06-2010, 04:40 PM   #60
Tech Addict
 
Join Date: Oct 2009
Posts: 654
Trader Rating: 5 (100%+)
Default

Quote:
Originally Posted by speedworks View Post
Search Losi 4 stroke on youtube i have 2 videos of my truck on there.
Thats frikkin sweet. LOVE the way it sounds. What kind of runtime can you get with that?
one8updragracer is offline   Reply With Quote
Reply

Similar Threads
Thread Thread Starter Forum Replies Last Post
Electric 1/8th Scale conversion kits. DJ1978 Electric Off-Road 19923 06-12-2017 05:16 AM
Kyosho VoneR Thread neons Nitro On-Road 12206 06-29-2012 03:19 PM
"Thump-8" 4 stroke 1/8th scale engine DP-buggyboy Onroad Nitro Engine Zone 91 07-14-2011 01:17 PM
difference between 4 cycle and 2 cycle engine? dragoneuh Onroad Nitro Engine Zone 35 01-05-2006 09:00 AM



Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are Off



All times are GMT -7. It is currently 07:24 AM.


Powered By: vBulletin v3.9.2.1
Privacy Policy | Terms of Use | Advertise Content © 2001-2011 RCTech.net