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2 bolt 23cc to 4 bolt 30cc


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as the title says really I’ve got a KM 23cc 2 bolt engine and can’t really find a rebuild kit for it in the Uk at lest I’ve come to the conclusion after a bit of reading and worked out the 2 bolt isn’t very reliable? is it worth buying a new complete 30cc 4 bolt from RCModelz I think about £160 or try and find a rebuild kit for the 23cc 2 bolt engine?

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Personally.... I'd buy neither of those options.

 

The KM 23cc 2 bolt is a cheap motor. It's not good quality, and while it does it;s job...it's not worth spending money on. Unless it;s genuinely all you can afford, in which case piston, rings and a head kit. But if you are looking at spending cash.... buy something better.

which is NOT a 30cc cheap motor. Thats a bigger cheap motor.

 

Where I would spend my money would be on a much better quality motor, which will provide a decent life and performance. In terms of quality in these motors, Zenoah are probably the best of the bunch, followed by CY.

 

For your £160, you could get this: https://www.innovative-rc.com/product_info.php?cPath=27_141_142&sort=1a&products_id=562

This is the 4 bolt version of the motor HPI fit to stock Bajas.

If you want to stick with RC Modelz choice of engines.... then save up a bit more and get this one https://www.rcmodelz.co.uk/engines/complete-engines/zenoah-g270rc-car-engine-4-bolt.html

 

I've run a variety of motors in my time, and you really can see where the costs are cut to sell an engine that looks similar for nearly £100 less and still make a profit.

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10 hours ago, Nitroholic said:

Personally.... I'd buy neither of those options.

 

The KM 23cc 2 bolt is a cheap motor. It's not good quality, and while it does it;s job...it's not worth spending money on. Unless it;s genuinely all you can afford, in which case piston, rings and a head kit. But if you are looking at spending cash.... buy something better.

which is NOT a 30cc cheap motor. Thats a bigger cheap motor.

 

Where I would spend my money would be on a much better quality motor, which will provide a decent life and performance. In terms of quality in these motors, Zenoah are probably the best of the bunch, followed by CY.

 

For your £160, you could get this: https://www.innovative-rc.com/product_info.php?cPath=27_141_142&sort=1a&products_id=562

This is the 4 bolt version of the motor HPI fit to stock Bajas.

If you want to stick with RC Modelz choice of engines.... then save up a bit more and get this one https://www.rcmodelz.co.uk/engines/complete-engines/zenoah-g270rc-car-engine-4-bolt.html

 

I've run a variety of motors in my time, and you really can see where the costs are cut to sell an engine that looks similar for nearly £100 less and still make a profit.

Ok I don’t mind spending the extra money on an engine that’s going to last and be better all round the only little hesitation is if I keep it 2 stroke and don’t do the electric conversion is that I’ll only use it a couple times a month with the petrol engine so would it still be a good thing to spend the extra ? 

 

sorry if my questions sound stupid but only really used electric RC’s so it’s still new to me the 1/5 scale petrol side of RC’s the one that I had years ago and loved was brand new so never got to fully understand the 1/5 scale ins and outs of them 

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Thats really a call you have to make yourself.

 

A better quality engine will be much nicer to use, will be more durable, and will give a better return through it's whole life. You have to decide if you are going to use it enough to make that worth while.

If you are only going to run it a few times, and then go brushless then I would think not... OR if you are undecided about what you are going to do, then selling a used motor never really gets you much of a return. Mostly becuase folks just never know what they are going to get, and whether it's just a worn out piece of junk..

 

Now...when you say you are looking for a rebuild kit... what state is your current motor in?

 

Might be worth picking up a used motor like this one : https://www.ebay.co.uk/itm/325553112476?hash=item4bcc7a459c:g:5zIAAOSw5h9jxUZR&amdata=enc%3AAQAHAAAAoE1ULyOOzv75jnl%2BQSIvfup9y994A6VDU0Pibmhg85Zh8dTVaVYCdtIsjOWhI0l6LvIZDV7aALIzgvkcW6bPDcpCpXq42W%2B4RKj7tOGtz%2BJxZEYYvq%2Bj97EklK4LohgDXqHIV4t6hsVNEz%2F9IO8CTTsPau6tXQL3KmCvEB9zR9PfBaAA9xVk5jFLvLDiAHlBsFCek398gsLol2U0rzqO%2FTY%3D|tkp%3ABk9SR8ropYXXYQ

 

But I would put only as much into the motor as you intend to get use from it.

 

The stock KM 23cc motor should be able to take basically any 2 bolt headkit. From what I recall of the older 2 bolts, 23 or 26cc kits are fine. 29cc ones come on a few designes and not all fit. So if the bottom end is good, get a head, piston and ring...gasket set...and rebuild the KM unit if you can do it for cheap.

 

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I don’t even know if the motor runs yet haven’t had time to find out 🙄I was looking for a rebuild kit just to refresh the motor if it’s indeed any good but as I’ll only use it a couple of times a month if I keep it 2 stroke I’m looking at all possibilities before I start spending the big money on engine's or ESC/motor/batteries 

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Fire it up and see where you stand 🙂

 

Parts/engines are not going to be difficult to obtain, so once you know what you have to start with, you can go from there. First thing you DO need to do is check what carb is fitted. Earlier KM engines came with a very poor clone carb which didn;t use the stock settings you will find quoted normally for these motors.
RC Modelz themselves started swapping carbs over on the cars they were selling to fit Walbro carbs from the outset. These are much better, make you motor run better, and are stock fitment to CY and Zenoah engines.

 

If the motor has a dodgy clone carb...that is well worth swapping.  But..really...before you go much further planning wise, you need to know what you have to start with. Fire it up....and if it runs good...run as is until you either brushless convert it or the motor fails. Then you can look at options with a better idea of where you want to get to. There are SO many options out there!

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11 minutes ago, Nitroholic said:

Fire it up and see where you stand 🙂

 

Parts/engines are not going to be difficult to obtain, so once you know what you have to start with, you can go from there. First thing you DO need to do is check what carb is fitted. Earlier KM engines came with a very poor clone carb which didn;t use the stock settings you will find quoted normally for these motors.
RC Modelz themselves started swapping carbs over on the cars they were selling to fit Walbro carbs from the outset. These are much better, make you motor run better, and are stock fitment to CY and Zenoah engines.

 

If the motor has a dodgy clone carb...that is well worth swapping.  But..really...before you go much further planning wise, you need to know what you have to start with. Fire it up....and if it runs good...run as is until you either brushless convert it or the motor fails. Then you can look at options with a better idea of where you want to get to. There are SO many options out there!

Great will do that 👍for all I know it might have a Walbro on it how can I tell is there markings on it to look for ? and what would be carb to get there’s quite a few from what I can see 

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The Walbro carb for stock, if I remember right was the WT668.

 

The KM motor I had had a carb with 'RuiXing' or somethjing similar looking on the bottom. This was a poor quality item. The proper item should have Walbro cast into the bottom plate on the carb.

Quite a few variants can be fitted, but I wouldn't go with a chokeless option.

 

Just don;t buy any of the cheap copies on E-Bay which are advertised as 'fitment for WT668' or similar. Make sure it is a real one.

https://www.innovative-rc.com/product_info.php?cPath=27_141_143&sort=1a&products_id=738

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17 hours ago, Nitroholic said:

The Walbro carb for stock, if I remember right was the WT668.

 

The KM motor I had had a carb with 'RuiXing' or somethjing similar looking on the bottom. This was a poor quality item. The proper item should have Walbro cast into the bottom plate on the carb.

Quite a few variants can be fitted, but I wouldn't go with a chokeless option.

 

Just don;t buy any of the cheap copies on E-Bay which are advertised as 'fitment for WT668' or similar. Make sure it is a real one.

https://www.innovative-rc.com/product_info.php?cPath=27_141_143&sort=1a&products_id=738

Cheers for the info and link I’ve just ordered the one you linked hopefully will get to mess about with it this weekend and find out what carb is on it and if it’s already got a walbro in I’ve got a new one as a replacement 👍

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