Valve Set Help

Mini Dirt Bikes & Pit Bikes Forum

Help Support Mini Dirt Bikes & Pit Bikes Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
Joined
Dec 11, 2008
Messages
9
Reaction score
0
Does anybody know the valve specs for a Loncin 150cc?

Also how can i get it at TDC? How can i turn the engine over slowly without using kick start?

cheers


img0561l.jpg


img0560awn.jpg
 
take your ignition cover off, turn the crank with a socket
 
i've read thats its something like 0.003 or 0.004 but some one will correct me if im wrong..Headmess should know or curtus Jake.
 
it's hard to get a straight answer for that one, just try .004/.005 or .003/.004 the pitpro mechanic told me .005/.007 but I didn't like the ticking noise
 
from my research it looks that way, there doesn't seem to be definite answer, cacktus jack explained it to me in great detail once, I could paste what he wrote to me here?
 
that would be good because i like to learn about these things in stead of posting shit anymore.. thanks
 
Dont know how much help cacktus jack or curtus jake will be but i know Cactus Jack knows everything about these engines :p

Thought id get in before skylar, lol


most of these bikes seem to have a clearance of .003 and .004
 
well hopefully jack come along and post something similar here because it was a long time ago and it's not in my PM box anymore, It was a really good read.
basically you just gotta go with what makes your bike run best, some like it tighter some not so much, pitpro running .005/.007 was for their worked race bikes
 
okay well 0.001 inch difference wouldn't destroy the engine, so i guess i'll just try 0.003 In. and 0.004 Ex.?

my engine is not OHC so is the only way to tell it's at TDC to watch when the valves rock? It's just kinda hard trying to get it to rock when all i have to turn it over is kick starter hah.

It's for a gokart i'm building anyway. i always thought it was a 250 but i measured it today and was disapointed. hopefully it will still haul arse??

Just incase anyone was curious:

img0562r.jpg
 
right!!!!.004 is a nice clearance, both sides inlet and exhaust

who da fug is curtus jake?:p

tdc, use a socket on the flywheel nut. there will be a mark somewhere...

and, now, seeing you havent started tackling the steering...take a look at this
Gokart Engine & Chassis Tutorials
then do some googling on steering geometry...you have camber, castor, kingpin inclination and ackermanns principle to work out. sounds complicated, but it isnt.

makes the difference between steering like a pig, and steering like a lotus....

and then, try to get as much weight over the front as possible... solid axles tend to make karts go in straight lines, especially when you got your foot down:)
 
yeah i figured out that it doesnt steer at all haha the front tyres just slide, ohwell. it's also gonna be a bone shaker offroad, no suspension. I'm not worrying about camber or castor.

yeah man i've already designed steering and my ackermann arms (with ackermann's principle) and yeah.


The engine is new and has run for about 2/3 minutes idling, when should i change the original oil, and how often should i change it regularly?

thanks heaps for help everyone
 
change it now!!!! then in a few hours! then again in twice as long...say 5 first, then ten, then....meh, whenever it gets a bit black looking

aye, geometries up to you, and damn i wish i kept some pics of the one i made.... could keep it sideways for hours, steered like a dream, and with 32 horsies at the rear:) oh, and who needs brakes?:p
 
Dont know how much help cacktus jack or curtus jake will be but i know Cactus Jack knows everything about these engines :p

Thought id get in before skylar, lol


most of these bikes seem to have a clearance of .003 and .004

i was close....she hasn't been on latly soo i dunno if she'll be correcting our spelling:(
 

Latest posts

Back
Top