murp24

Ye only a 50, was hoping to get a h100 engine in it but they dont come cheap so that not going to happen. Good little bike to build, all straight forward when you know what your doing. You can also use parts from a number of bikes such as the MB50, H100, MTX50 and CR80. The MBs and MTs including the MTXx are basicly the same bikes, same frame, and the MB is just the more road going version of the MT. With the CR80 you can use the swing arm and various other parts.

it worked, thanks mate. Feels a bit rought but it works non the less.

Hi mate, i will give that a go.

She LIVES! Spent a few hours in the garage this morning when my parts came and fitted the new piston rings, new NGK spark plug cap and new cone air filter and she fired! Finaly! Just need to sort out the clutch and my sticking front break lever and the restoration complete. Would be nice to get some side panels but seem to be pretty rare.

It might be worth getting a new spark plug cap. Had a similar problem with a peugeot blaster and spark plug cap wasnt waterproof.

it was chiped mate, that is my old piston. got a new one.

Scratch is only slight, and the piston is a mirror image on both sides so dont think it realy matters which way it is fitted, theres a few pics of it on the first page.

Cheers mate will keep you posted. The scratch is slight just i dont think its anything major, just a guesstimate maybe two eighths of a mill deep wouldnt know for sure. When I get the bike going again will upload some photos of the finished product.

Turned out that one of my rings (top one) had snapped and has grooved a minute line in the bore, also when i put the piston in with just the 1 ring on and rut it into the bore with the 'in' on the top of the piston facing the exaust rather that the engine/manifold side it moves more freely. Now to find some more rings

Thanks Tango. Will give that a go tomorrow. The piston and bore are standard size 39mm and I bought a newer but same piston and fitted that with 2 old rings on it and now it has 1 old ring and 1 new, the old ring was in quite good condition but will give it the once over tomorrow, im just praying that the new one hasnt snapped or something because they arent easy to find.

remove air filter, put hadn over the intake to the carb... "Choking" unlikely the kickstart, but you can try "bump starting" the bike... 2nd gear, run along with the bike, let the clutch out... back wheel turns engine, a healthy bike would start. I will try bump starting it before i strip it, also tryed choking it earlier and nothing. Got a problem with the clutch, it dosent seem to be engaging, i have ajusted the clutch lever to the specs in the work shop manuel but when i pull it it seems fine and springs back, i can see the clutch lever and spring working fine but when i put it in gear the bike wont move as if clutch isnt engaged. When the bike was running a few weeks ago i tryed putting it into 1st with clutch in whilst engine was running and it stalled. Any ideas? Sorry for being a bother, im not a mechanic just a 21 year old building a bike for the first time

Have a continuous spark when kicked so that seems fine? I have 1 new ring and 1 older ring on the piston as one was snapped, and i believe they are on correctly. Not sure how to choke a carb, do you mean block air in take (air filter). Also My finger smelt of peterol when i was testing compresion. Im starting to believe the foot rest is to blame stopping me from getting a good kick.

Hi Tango I checked the compression by putting my thumb over the hole and have some one else to kick it. There is compresion there but it didn't exactly blow my thumb off the hole. Never removed the needle circlip is in right slot and the carb needs ajusting but not familiar with how to do it without the bike running. I noticed yesterday that when the bike is kicked the kick starter hits the foot peg, now I am not sure if it did this before and was wondering whether or not when I droped the engine to remove bore that when I put it back in in might be a little off some how. So im not sure if it is just me but I cant recall whether it was like this before. Could it be that when I am kicking the bike it it needs to go an extra few mill or so to get the right kick to start and the engine is just off a little? If I cant get it sorted today Im going to take the engine out tomorrow, check carb, cylinder, bore and piston. Would a CDI unit stop my bike from starting if it was faulty even though there is no battery because I still get the spark and was wondering was it cutting it out maybe?

In away im quite disapointed as I was hoping that would be the problem. Any other sugestions? I just dont understand it.

Hi Joeman, thanks for your post. I took the spark plug out and look into the hole with a mirror and the 'IN' on the piston is facing the rear of the bike (towards engine) as it says in manuel, however I read somewhere that it might have to face the exaust side? ........................ Not familiar with that engine, but "IN" would likely refer to the "inlet" side of the engine, so as long as "IN" is facing the carb (back of the bike) , you very likely have it round the correct way. However, as another check, if you take the exhaust off, you'll see the piston going up and down, and if you see transfer ports in the skirt of the piston, then you have the piston in backwards! Hi again Joeman I havent took the exaust off yet as I thought I should take some photos of the old piston which I replaced some time ago because from where the exause is situated and with both sides of the piston looking identicle I am not sure how that check would be done. The old piston has a bit of damage to one of the scirts in one of the photos. Whilst giving the bike the once over I took out the CDI Unit and consulted the manuel and checked each connection to the UK specs given in the manuel. Some of the conections gave right reading but some didnt give the right readind or no reading at all. So I was wondering could this be the problem even though there is no battery? [album]360[/album] [album]359[/album] [album]358[/album] [album]361[/album] Second photo is one with damage.

Hi Joeman, thanks for your post. I took the spark plug out and look into the hole with a mirror and the 'IN' on the piston is facing the rear of the bike (towards engine) as it says in manuel, however I read somewhere that it might have to face the exaust side? ........................

Hi Tango. Jet is fine I striped the carb and was spotles, took it apart the other day to check the jets again and just the same. Could it be anything to do with the throttle or idle screm needing ajustments on the carb?

Thank you for the reply much apreciated. The fuel tap is in the the ON position and there is no obstruction from the tank, new fuel is in the tank and ye there is fuel in the float chamber. All lines are connected to the carb, one was left off and is now conected which was a breather. Still wont start, thought asmuch. The only thing I have not tryed is putting a few drops of peterol in the bore and then trying to start it.

Hi everyone. I am having problems with my Honda MT50 Rebuild, it has a lack of starting after installing new piston rings, dont thing that is the problem. I have been restoring & rebuilding a Honda MT50 and had the bike running fine apart from it idling a little fast and being a bit rich. Until the other day when I replaced one of the worn piston rings with a new one as one of the new ones came pre snapped . I put the bike together and slowly pushed down one the kick start and all seemed fine, piston moving fine in bore. However when I came to trying to start the bike, nothing. All i get is the sound of the air filter sucking air in, the engine turning and piston moving up and down. I took the spark plug out and it was dry as if no fuel is geting to it, plug sparks fine. Bike has never had use of any of its electrics, its purely off road as there is no battery. Any help would be apreciated. Thanks