Ducar 138 engine specs

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gtrtorana

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HI, i'm sorry if this question has been asked before but I am after any info on the Ducar 138 engine. I purchased my first mini bike new in 07 and it was advertised as a 125 but when I picked it up, it had 138 cast into the barrel. Does anyone have any specs on this engine and is it actually a 138 or a 125?. Thanks.
 
and theres a few varieties of them to.

start with posting your engine number, but usually you have to remove the head and measure it all
 
what happened to ducar.. i remember when they started bring out the 70cc, 90cc, and 125cc they were awesome lol.
 
and theres a few varieties of them to.

start with posting your engine number, but usually you have to remove the head and measure it all

The engine number is 70416391. Can you tell what the engines true specs are from this number? What are the variations in the Ducar 138? Thanks for the help.
 
wrong engine number mate.. should be the one above that 1
99% of the time you can at least tell the bore size but i have witnessed engine number saying 53mm piston and its only 52.4..
but another thing you can do is punch the engine number into good old google and you should be able to find some good info on it
 
Sorry about that. Engine number is TZH157FM1. Can you tell anything from this? I will have a look at google now for any info. Thanks again
 
TZH157FMI. Double checked and last didget is a I, not a 1. Not sure if that makes a difference. This bike was sold to me new and was advertised as a 125 and when I saw the 138 it threw me. I never complained as 138 sounded better than a 125.
 
It has a cast bore, not alloy.

Also found this
It's a Tian Zhong Technologies engine ... probably with a Lifan clutch cover plonked on it ... and it's probably only a 107 too ... LOL ... IF the cylinder studs are only 6 mm ( the head nuts are only 10.5 mm across the flats) ... it's definitely a 107 ... Longer stroked engines need 8 mm studs to avoid blown head gaskets ...

I bought a brand new full auto electric start 107 off A-1 Importer and its engine # is TZH152FMH ... It was delivered in a Tian Zhong Technologies box ... I won it on ebay one Monday night for $120 ...

The cam end plate on 'em has really thin fins ... Did you buy that engine new ? ... IF not someone could have changed the side cases and head ... or maybe some shady backyard assembler over in China is slapping their own engines together from parts sourced from here and there ... The last letter on the engine #'s designates the series of the engine ... ie mine is a "H" series ... later model engines were "I" series ... and then came the "J" series ... Theoretically ... the next series should be FMK's ...

Something's a bit sus with the "57" ... I'll bet it hasn't got a 57 mm bore ... especially since you can only bore to 54 mm with the 110/120 small valve head stud pattern ... The case bore is only 56 ~ 57 mm and the studs are really close to the edge ... Maybe some newby worker stuffed up the stamping of a batch of cases at the Lifan factory so they flogged the cases off cheap to Tian Zhong ? ...

I've seen tons of stuff that "appears" to be good go into the scrap bins at factories due to slight machining tolerance / production errors ...

From the flywheel side it looks extremely Loncin/Ducar like ...
 
also does it have a cast iron bore or alloy? im guessing alloy
It has a cast iron barrel/bore. Does this make a difference?
 
Man ... I couldn't have given better info on TZH engines myself ... :D

It's not a Ducar ... I've got a new 107 semi auto and it's engine # is DJ152FMH ... The number pad is bare alloy and the #'s are a series of dots/punch marks ... It looks to be a well made engine whereas TZH's are cheapish looking ...

BTW I sold that TZH 107 full auto to an acquaintance to repower his TZH 70 cc powered quad bike ...
 
Looks like I will only know the true engine size when the head is off. At least then I can work out if it is a 107, 124 or 138.
 
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