Reliable $100-$200 21-26 BB Pull-start

[Bryson]

That pro version hauls ass man my friend has it in a xtm buggy and o wow it flys.

Bryson

 

[AC48]

Found it! PM sent olds...

 

[olds97_lss]

Thanks AC48... the large head on the XTM 24.7 is too fat. It's fatter than the axial head, but shorter. Since it sits at such an angle in the revo, the side of the top fin sticks up as high as the stupid axial!

I'm planning on making a new roll bar anyway, but the small head your sending me will save me from having to do it before this weekend when it's going to be warmer and I can break it in.

 

[SMaxxin]

I'm not sure if it's smaller but the head from an HPI .21/.25 will fit the XTM engine.....I have an XTM with an HPI head on it mill sitting in a drawer. It came as a spare with my Savage but I never really checked it out.

 

[psunitro]

The GS .25 that they put in the old SUT's are the same thing as the .247. May help in parts search.....

 

[debo350]

the mach 28 or 27 will give you what you need, idel and everything, the motor is very reliable after sitting for 7 montrh at bottom dead center!!!!!!!!!!

 

[olds97_lss]

The 24.7 has been working well so far. Holds a tune, runs well, idles well, broke in pretty painlessly, gobs of power and it seems to be pretty economical as far as fuel goes.

I've only run about 1/2 gallon through it, but after that first quart of breaking in, it's been a blast. 15/36 gearing, 3.3 chassis and standard ratio trans and it still pulls a solid wheelie when it hits second.

I've learned a bit of throttle control. The 21RG wasn't anywhere as punchy as this is. I'm glad I decided to go BB. The 18TM is a good engine, but there is no replacement for displacement...

 

[debo350]

yeah I've been looking at that motor, and XTM's 28,what do you think about their 28 BB

 

[olds97_lss]

Couldn't say. If it has as much power as the 24.7, it's a strong engine. I can only assume it's got more torque since it's larger.

 

[debo350]

Thank you buddie, I went to my lhs and got the all dependable O.S 21 rg the old one that has been around for a long while, and I know for a fact that O.S always under specs their motors, and from what I hear guys say that they get to about 8 -10 gallons on these motors, and my lhs still can get a piston and sleve for this motor:sick: :sick:

 

[olds97_lss]

I went to my lhs and got the all dependable O.S 21 rg the old one that has been around for a long while

Apparently you didn't run across my other thread.

https://www.rcnitrotalk.com/forum/showthread.php?t=46481