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nathan k
05-31-2012, 08:07 AM
Hi,

After the circlip coming loose and destroying my malossi MHR cylinder I bought a metra kit 70cc kit. whenever i turn it over with the sparkplug in the piston hits the spark plug. I am using Br10es and also have a Br8es. any ideas? if i unscrew the spark plug untill it dosen't hit the cylinder it is really loose and hardly screwed in.

Thanks

Nathan

camb00
05-31-2012, 08:37 AM
Put another gasket ander the cillinder,

weasel221
05-31-2012, 08:46 AM
use a shorter plug!!! the 'es' plugs have a long thread body, there is a shorter plug, 'eg'?? to may braincells ago....lol

RS_Patrick
05-31-2012, 09:17 AM
use a shorter plug!!! the 'es' plugs have a long thread body, there is a shorter plug, 'eg'?? to may braincells ago....lol


Not a good idea unless the manual/boolet of the Metrakit cilinder says he needs a shorter plug (HS instead of ES) but thats unlikly.

I am guessing he installed the gaskets incorrectly, fitted only the thinnest set maybe?

Are you sure you got the electrode gap set correctly? 0,6mm???

nathan k
05-31-2012, 10:45 AM
the gap needed is too much for gaskets to space out, I installed everything supplied in the kit and even checked again just now when I checked the piston for any scratches or chips.

going to order a HS plug, not sure about the electrode gap? it's a cm or two that's needed though. quick question, do I need a BR9 or 10? I was thinking 10 because it will almost always be used on fast roads to and from college.

RS_Patrick
05-31-2012, 12:45 PM
2cm??? wtf? thats imposible mate if its so much (more than 5mm) than you got the wrong cilinderkit, wrong piston, (maybe someone mixed stuff up in the shop?) or you got a long stroke crank in there mate.

If you fit a HS plug in a head that needs a ES its not gonna last, the edge of the hole and the threading in the hole will burn away and melted particles from that can seriously knacker your piston and barrel.


btw, how do you know the plug is touching the piston?

nathan k
05-31-2012, 02:39 PM
2cm??? wtf? thats imposible mate if its so much (more than 5mm) than you got the wrong cilinderkit, wrong piston, (maybe someone mixed stuff up in the shop?) or you got a long stroke crank in there mate.

If you fit a HS plug in a head that needs a ES its not gonna last, the edge of the hole and the threading in the hole will burn away and melted particles from that can seriously knacker your piston and barrel.


btw, how do you know the plug is touching the piston?

I can hear it, and also when the plug is only slightly done up I can see it get knocked.

The old kit was 80cc although I can not find anything to do with a crankshaft in the paperwork I have for it. I have a bill for a 80cc and it being fitted even a letter saying the brakes are adequate from the mechanic but no mention of a crank.

It's just under 1cm sorry not 2.

I looked over everything supplied with the kit and found nothing definitive relating to spark plug size, In the Metra Kit information it did say to use a "BR9" plug but did not go into any more detail.

Glen1990
05-31-2012, 03:53 PM
may of been a 80cc kit that needed a longer crank? :S there is some...

RS_Patrick
05-31-2012, 04:19 PM
If you dont tighten the sparkplug up fully and turn the engine the plug always moves a little from the presure behind it...

What happened to your other kit? maybe the krank is knackered and its that wich your hearing?

Use a caliper gauge to mesure how much room there is from the top of the cilinder to the piston wen its fully up.

I really think its highly unlikely that your sparkplug would be hitting the top of the piston mate, because if that was the case it probably would be hitting the outer edge of the cilinder head also.

Only way to find out whats goung on is to pull the head of the cilinderkit and look at the head with the plug in there and the piston, you can put a bit of paint on the electrode and turn the engine round and take the head off to see if theres any paint pressed on the piston.

I really dont think the plug is hitting the piston, unless the electrode gap is way to big or the crank is really messed up.


@Glen1990, if it was a Longer Stroke cilinder the piston wouldnt even get near the top mate with a stock crank, but if he has a normal stroke kit, and a longer stroke crank than hese got a problem, but like i said above i dont think anything is really hitting the piston at all (unless the crank is knackered really bad)

nathan k
05-31-2012, 04:28 PM
What happened to your other kit? maybe the krank is knackered and its that wich your hearing?


The circlip came out and lodged itself between the rings and the cylinder wall, was basically a new kit. will take off the cylinder head and put a photo up of what it looks like with the spark plug fully screwed in as soon as I get a chance. can't believe I didn't think of doing that before I put it all back together!

RS_Patrick
05-31-2012, 04:31 PM
Now i remember yeah, well if anything of that debris or circlip it self got into the cranks big end bearing that would seriously mess it up, oh, and btw, are you sure you got the right needlebearing installed for the pistonpin???

nathan k
05-31-2012, 04:44 PM
Now i remember yeah, well if anything of that debris or circlip it self got into the cranks big end bearing that would seriously mess it up, oh, and btw, are you sure you got the right needlebearing installed for the pistonpin???

is the needle bearing the same as a small end bearing? the one at the end of the crank? if so then I'm not sure, I used the one that was already in there as it seemed to fit fine and looked in great condition.

camb00
05-31-2012, 05:17 PM
Which cillinder head are you using?

nathan k
06-01-2012, 06:04 AM
Which cillinder head are you using?
I bought it as one kit, http://www.adrenalin-pedstop.co.uk/p-Metrakit_MK_70cc_cylinder_kit_for_Minarelli_AM6_en gines-5034.aspx

camb00
06-01-2012, 08:29 AM
A new cylinder head is included with all the necessary gaskets and fittings and a technical data sheet that tells you things like squish clearance and torque settings.

chn you scan the sheet or take picture

RS_Patrick
06-01-2012, 11:51 AM
I really think somethings broken or the Electrode of the Plug is bent to far out... p.s. the plug you got doesnt happen to be a BR9ES-15???

That kit should be right wen you fit it with the gaskets installed, on top of that its a low compresion kit, so theres a good bit of space left above the piston before it would hit the plug, so its not squish or gasket related, i even think that with out any gaskets the sparkplug should stay wel clear of the piston with that kit.

nathan k
06-13-2012, 02:23 PM
I really think somethings broken or the Electrode of the Plug is bent to far out... p.s. the plug you got doesnt happen to be a BR9ES-15???

That kit should be right wen you fit it with the gaskets installed, on top of that its a low compresion kit, so theres a good bit of space left above the piston before it would hit the plug, so its not squish or gasket related, i even think that with out any gaskets the sparkplug should stay wel clear of the piston with that kit.

Well it turns out you guys were right!:o

So what could be causing a load clunking/knocking noise when i turn it over? i am too afraid to start it in case it's something serious and i fuck it all up again

The kit is a 70cc metra kit and has never been run so could it be because it's new? it was fine before my old kit blew up.

RS_Patrick
06-13-2012, 04:47 PM
Crankshaft, like i said, debris probably did get in there.

nathan k
06-14-2012, 06:05 AM
Crankshaft, like i said, debris probably did get in there.

First i've got to admit something, it's not a rs 50. it's a motorhispania furia. I'm very tempted to just sell the bike for parts and get a rs 50, which is the bike i really want. or possibly send the engine off to a rebuild service get a new crank and bearing (about 200 pounds) then swap it out with a rs 50 with a end of life engine.

not quite sure where to go from here now, or if it's even worth pouring more money into the bike when it's a rs 50 i want anyway!

Oh and thanks for everyone's help hopefully I wont need anymore!

RS_Patrick
06-14-2012, 06:45 PM
Its the same engine as the RS50 mate.

I really think its the crank (big end) wich would be a reall shame because you already put time and money in a new cilinderkit.

Big End makes a noise that kinda sounds like somethings hitting the cilinderhead, and it can even really hit the cilinderhead if the big end bearing is really totaly gone because of the amount of play the conrod than has on the crank.

nathan k
06-16-2012, 04:45 PM
Its the same engine as the RS50 mate.

I really think its the crank (big end) wich would be a reall shame because you already put time and money in a new cilinderkit.

Big End makes a noise that kinda sounds like somethings hitting the cilinderhead, and it can even really hit the cilinderhead if the big end bearing is really totaly gone because of the amount of play the conrod than has on the crank.

That would make sense, and i'm a bit annoyed to say the least!
I'm sending off the engine to these guys on Monday and fingers crossed it's just bearings http://www.ebay.co.uk/itm/Aprilia-RS50-RS-50-RX50-RX-50-Engine-Rebuild-service-/190668653372?pt=UK_Motorcycle_Parts&hash=item2c64bcc33c#ht_2690wt_782

I've really enjoyed working on the bike and I've learnt so much from my mistakes. I'm tempted to do an engine swap with an rs 50 if I can find one cheap enough. although it's my only mode of transport come august so i really need just get it going and leave it.

I really want to have a go at an rs 50 engine swap, I just don't think I realistically have the knowledge. Also not sure if i could get away with saying it's still a 50? It's the electrics that would hold me back though. so i could possibly use a complete donor bike and then use all of the electrics and not have to integrate anything. anyway i'm going to start saving because 50cc is simply not enough for me! I need more speeeeeed :lover::lover:

RS_Patrick
06-17-2012, 10:51 AM
A rarther keep the AM-6 engine in there, its the fastes 50cc engine available, parts are easy to get and you can get 75mph or more out of it with out to much trouble with really fast acceleration (Golf GTI wont keep up) so theres enough you can do with these engine with out "raping" the bike.

nathan k
06-17-2012, 11:22 AM
A rarther keep the AM-6 engine in there, its the fastes 50cc engine available, parts are easy to get and you can get 75mph or more out of it with out to much trouble with really fast acceleration (Golf GTI wont keep up) so theres enough you can do with these engine with out "raping" the bike.

very true, I'm going to wait until winter so i can build up my experience first anyway then I might start a rs 50 (125) project. Would be nice to have a little bit more power for overtaking though

chrism15
06-17-2012, 12:14 PM
very true, I'm going to wait until winter so i can build up my experience first anyway then I might start a rs 50 (125) project. Would be nice to have a little bit more power for overtaking though

your not suggesting a rs 50 frame with a 125 engine?

read the sticky thread

nathan k
06-18-2012, 09:43 AM
your not suggesting a rs 50 frame with a 125 engine?

read the sticky thread

I am! just not a rs 125 engine ;)
I know a yz125 engine will fit well with not too many frame modifications. it's just the electrics the would prevent me from doing it, i'd have no idea where to even start with them!

chrism15
06-18-2012, 11:37 AM
I am! just not a rs 125 engine ;)
I know a yz125 engine will fit well with not too many frame modifications. it's just the electrics the would prevent me from doing it, i'd have no idea where to even start with them!

mate dont, the swingarm will snap or the frame will twist - and you think a yz 125 engine is less powerful than a rs125 engine? the yz is more aggressive than the rs 125 so it will be even more likely to snap, twist ect

if you want a bigger engine get a yz 85 engine, kx 85 engine, erm and theres a couple more i cant think of but guys have done that safely on here, 125 is too much trust me!

theres a dude who died doing a project like this (only different bikes and bigger engine) he was on the forum apperantly as "spike" rip

never knew spike through here but all the same we dont want another, be safe about it ;)

Read the sticky thread!

http://www.apriliaforum.com/forums/showthread.php?114226-Can-an-Rs125-engine-fit-into-an-RS50-frame

there was one person a few yrs back that converted a rs 50 into a rs 125 streetfighter and did a very good job too and some thought it would even last because it was well thought out but after a few weeks he was never heard of again so that gives you a clue something went badly wrong

Glen1990
06-18-2012, 12:05 PM
hmm my self i think the frame will be fine with a 125 many people have done it and been fine clearly is gonna be stupidly powerful my self ill rather tune the am6 engine much more fun

chrism15
06-18-2012, 04:16 PM
many people fit yz 85 engines and kx 85 engines but the am6 frame just wont take the strain of a 125, certanly not the yz 125 coz that really is a aggressive punch but loads of people try to fit rs 125 engines in thinking the frames are exactly the same or even spend weeks purely modding the frame to make it stronger but it just wont have it

there was a bloke who had his 3 weeks (toke him 2 months work with parts all set to go) aprilia rs 50 engine with aprilia rs 125 engine, well anyway the frame litrally twisted after 3 weeks

if you wanna do a engine transplant for more power look into 85cc, YZ 85 willl pack plenty of punch (a mate of mine had a yz 85 which was mental enough as it was! let alone the 125) kx 85 has been done also, cr 85 has been done too

rs250lape
06-18-2012, 07:08 PM
the frame will stay togather fine when they test these frames they way over test to make sure they will be safe . There is a guy who did a yamaha 125 in a 50cc and it is fine. he is also selling it to i beleive. look on here and bay area twostroke.com .. they make a 110 cc kit out there for these .. also how do you twist a frame if you launch the bike will wheely so i dont know how you could hold it down enough to put stress on it. not trying to be a wise ass but doesnt sound right. I have friends with atv rated for 200cc engines and put cbr600 motors in them. stupid but they stay togather.

chrism15
06-19-2012, 12:55 AM
http://www.apriliaforum.com/forums/showthread.php?114226-Can-an-Rs125-engine-fit-into-an-RS50-frame

rs250lape
06-19-2012, 01:30 AM
Yes that is a sticky but putting a 125 yamaha motor in it possible and has been done go on you tube itsd there the guy lives in california and knows TORA TORA

Glen1990
06-19-2012, 03:40 AM
yeah it will hold up fine with a 125 yz

nathan k
06-19-2012, 04:05 AM
the frame will stay togather fine when they test these frames they way over test to make sure they will be safe . There is a guy who did a yamaha 125 in a 50cc and it is fine. he is also selling it to i beleive. look on here and bay area twostroke.com .. they make a 110 cc kit out there for these .. also how do you twist a frame if you launch the bike will wheely so i dont know how you could hold it down enough to put stress on it. not trying to be a wise ass but doesnt sound right. I have friends with atv rated for 200cc engines and put cbr600 motors in them. stupid but they stay togather.
can't seem to find him, do you have a link?

Also anyone know if I can just hook up the lights directly to the battery and just charge it every night, would make it a lot simpler

Glen1990
06-19-2012, 04:10 AM
http://www.youtube.com/watch?v=ldsN8K69_0o

rs250lape
06-19-2012, 06:02 AM
http://www.apriliaforum.com/forums/s...d.php?t=231722

nathan k
06-19-2012, 09:55 AM
around 2200 pounds plus shipping to the uk, a little over budget :(
Plus was a year ago, probably sold by now

oh and no way i could get away with it being a 50 as would need to be inspected, registered etc

rs250lape
06-19-2012, 11:32 AM
ya i hear you but you knoe it can be done

nathan k
06-19-2012, 11:56 AM
ya i hear you but you knoe it can be done

It can, and it will! selling my rib and downgrading so i can afford a bit of project. not sure if it will be a rs 50 with a 125/250 or a 125 with a 250/400. after all I can drive a 125 in a year anyway so would be nice to build something I can use for 2-3 years. anyway i'll start a thread once i've done all my research and have bought the donor bike.

chrism15
06-19-2012, 12:44 PM
yes i agree it can be done, so can the rs125 engine but the yz engine takes less modding

the yz will pack more punch than the rs engine for sure purely for it being more aggressive

id play it safe with

yamaha yz 85 engine

kx 85 engine

cr 85 engine

nathan k
06-19-2012, 12:57 PM
yes i agree it can be done, so can the rs125 engine but the yz engine takes less modding

the yz will pack more punch than the rs engine for sure purely for it being more aggressive

id play it safe with

yamaha yz 85 engine

kx 85 engine

cr 85 engine

then there's no point, A well tuned rs 50 engine will be along the same lines.

YZ 125 me thinks, dirt cheap around here anyway. (get it? i'm hilarious!)

rs250lape
06-19-2012, 01:20 PM
it would be more of a pain in the ass to install a rs125 engine and there is not much difference in power as dirt bikes are more geared for low quick bursts and that can be delt with by using different sprockets