Post by: Stusmoke on June 22, 2012, 03:50:09 AM
Cheers guys.
Post by: msmola2002 on June 22, 2012, 05:22:56 AM
Post by: Stusmoke on June 22, 2012, 05:27:03 AM
Am I going to need sealant to get it back together?
The cylinder was EXTREMELY hot for a two stroke I might add, I think hes running a fairly low octane fuel
Also, the kickstarter is VERY easy to move through its strokes. It doesn't feel like it has much compression at all.
Thanks Mola
Post by: factoryX on June 22, 2012, 10:25:54 AM
Post by: Stusmoke on June 22, 2012, 10:43:59 AM
Post by: scotty dog on June 22, 2012, 11:25:55 AM
sell ya 250 Stu and bomb the 125, surely you could get enough to fully rebuild the engine, slap on some new rubber, tidy it up and youll be motoin in no time
got a pic of it??
Post by: Stusmoke on June 22, 2012, 01:19:09 PM
Post by: Super Trucker on June 22, 2012, 06:20:08 PM
Post by: SachsGS on June 22, 2012, 06:41:57 PM
Post by: cnrcpla on June 22, 2012, 10:16:32 PM
Post by: Stusmoke on June 23, 2012, 01:09:46 AM
When I first rode it I rode it like my 250 and it felt like my XR100... The lack of bottom and mid was insane. But once I remembered it was a 125 and got it up to the upper ranges, WOW. I took off in a cloud of dust.
Never reuse base and head gaskets. Honda cr 125,s have 2 diff. sized cylinders a and b. Even if you put a honda a size piston in a a size cylinder, the honda piston is too small, causing piston slap. The alum. frame resinates it further. A forged piston is also much louder than a cast piston. Do a google search, some riders are using Husky pistons, in there 2000-03 cr125,s. I think the Vortex piston for a cr125 is the same size as a Husky piston. There is a performance increase when you get the correct size piston. Your prob. asking your self, why did honda put the wrong size piston in, part of the reason is it,s more diff. to seize the motor, from the wrong jetting. More or less the stock piston is for break in purposes only. A play rider that never jetts his bike should stick with the stocker.
Well thanks Honda
so look into a vertex piston kit? Roger that. Cheers mate.Cheers guys, I'll get a pic up soon to.
Post by: Jeram on June 23, 2012, 02:45:12 AM
Post by: luthier269 on June 23, 2012, 02:49:57 AM
Post by: Stusmoke on June 23, 2012, 04:50:03 AM
Thanks
Post by: TMKIWI on June 23, 2012, 05:43:56 AM
You have leaking water pump seals.
Check your gearbox oil for water as well.
Rule of thumb with any bike I buy is do not trust the previous owner.
Put fresh fuel in straight away, check all fluids and then fire it up.
By the sounds of it stu I would pull the barrel of as a bare minimum and go from there.
You are going to need a water pump seal kit as well.
Best you fix everything now before it turns to custard.
Post by: Stusmoke on June 23, 2012, 06:19:05 AM
The hole where the coolent is draining from is supposed to be there.
You have leaking water pump seals.
Check your gearbox oil for water as well.
Rule of thumb with any bike I buy is do not trust the previous owner.
Put fresh fuel in straight away, check all fluids and then fire it up.
By the sounds of it stu I would pull the barrel of as a bare minimum and go from there.
You are going to need a water pump seal kit as well.
Best you fix everything now before it turns to custard.
My thoughts too. I don't trust previous owners either. But the jokes on him for selling me a dodgey bike, cos I kept the left crank case and silencer from the wreck. hopefully that'll pay for the damages
Im gonna go pull the top off her now. The spark plug seemed to be in decent nick besides some carbon fouling so its hopefully a top end job. and the water pump seals aswell.
Post by: Stusmoke on June 23, 2012, 08:25:09 AM
Never reuse base and head gaskets. Honda cr 125,s have 2 diff. sized cylinders a and b. Even if you put a honda a size piston in a a size cylinder, the honda piston is too small, causing piston slap. The alum. frame resinates it further. A forged piston is also much louder than a cast piston. Do a google search, some riders are using Husky pistons, in there 2000-03 cr125,s. I think the Vortex piston for a cr125 is the same size as a Husky piston. There is a performance increase when you get the correct size piston. Your prob. asking your self, why did honda put the wrong size piston in, part of the reason is it,s more diff. to seize the motor, from the wrong jetting. More or less the stock piston is for break in purposes only. A play rider that never jetts his bike should stick with the stocker.
I pulled the cylinder head and barrel just now. Getting the barrel off was a nightmare though. Anyway all is good in there, piston looks brand new. I'd be willing to bet you're on the money with the incorrectly sized pistons. When I was looking at new piston kits it said the stock bore was 54 mil. When I looked on the engine, it informed me it was 54.5 mil. So I'm pretty sure you nailed it thanks. And TMKIWI the tranny oil is a sickly grey color so you were on the money with the water pump seals too. I'll drain the tranny oil tomorrow but do I need to do anything do the tranny other than replace those water pump seals? Also, will riding this bike with that .5 mil space destroy the cylinder? I would've thought it would. I'm gonna be screaming it till the cows come home too it will be shown absolutely no mercy.
Thanks guys
Post by: Jeram on June 23, 2012, 09:10:45 AM
all it'l is the skirt or crown to catch one of the ports and it'll be all over, im suprised its still in good condition!
Post by: Stusmoke on June 23, 2012, 09:21:38 AM
yeah will destroy your entire motor if you ride it any more.
all it'l is the skirt or crown to catch one of the ports and it'll be all over, im suprised its still in good condition!
Thats what I thought
Thanks again honda, you guys always come through on good ideas
http://www.motosport.com/dirtbike/WISECO-PROLITE-2STROKE-PISTON-080-OVERSIZE
will that do for a piston replacement?
Or perhaps: http://www.wiseco.com/ProductDetail.aspx?ItemID=676M05450&ModelID=121&ModelYear=2001&AppID=4187
Are they the same thing? It definitely says 54.5 mil bore just under the left hand side crank case cover. Thanks guys
Post by: SachsGS on June 23, 2012, 04:26:40 PM
Coolant leaking into Japanese transmissions is a HUGE problem.The Japanese trans. are typically cast,machined and case hardened and when you loose the lubricity of tranny oil the case hardening is then pounded off and you are left with a mess. Seen it many times.
Post by: Stusmoke on June 24, 2012, 01:44:42 AM
Measure the cylinder,piston and ring end gap so that you know for certain the condition of the top end.
Coolant leaking into Japanese transmissions is a HUGE problem.The Japanese trans. are typically cast,machined and case hardened and when you loose the lubricity of tranny oil the case hardening is then pounded off and you are left with a mess. Seen it many times.
A good idea, I'm not runnning it at the moment so I'm gonna drain the tranny oil today. I should also add that the cylinder looks likes its sleeved, heres some pictures. Sorry if its a bit difficult to see
Its hard to see the piston there but it looks fine.
It looks like its sleeved, whats the verdict? in the event it is sleeved, wouldn't that make the piston the CORRECT size?
Post by: Stusmoke on June 24, 2012, 09:22:32 AM
How in the name of christ this engine hasn't shredded itself to pieces is beyond both me and what one could consider to be logical. I stuck that mother to its rev limiter several times when I was checking it out and rode it pretty hard. Its unbelievably unlucky that it didn't blow. Yeah, I definitely said unlucky. If it had blown I would've told him to gtfo my property would've saved me alot of trouble.
So I guess its time to split the cases huh? What am I looking at fellas? Would I just be able to tighten the shit out of everything or will it all need to be replaced? Also, all the tools I will need to pull off this repair.
I will have a video up next post. Thanks guys I appreciate you taking the time to help me out.
Post by: Stusmoke on June 24, 2012, 10:13:29 AM
Worlds worst rebuild.
Post by: Recovered on June 24, 2012, 09:17:54 PM
Post by: 2T Institute on June 24, 2012, 10:36:52 PM
Hahahahahaa okay so theres one mil at bare minimum of side to side play on the crank end of the conrod, and the same thing with the piston end. I guess we know where the cronic rattling noise is coming from right?
How in the name of christ this engine hasn't shredded itself to pieces is beyond both me and what one could consider to be logical. I stuck that mother to its rev limiter several times when I was checking it out and rode it pretty hard. Its unbelievably unlucky that it didn't blow. Yeah, I definitely said unlucky. If it had blown I would've told him to gtfo my property would've saved me alot of trouble.
So I guess its time to split the cases huh? What am I looking at fellas? Would I just be able to tighten the shit out of everything or will it all need to be replaced? Also, all the tools I will need to pull off this repair.
I will have a video up next post. Thanks guys I appreciate you taking the time to help me out.
Side play in the rod and piston is correct. Piston to bore clearence is what needs to be checked.
Post by: Jeram on June 24, 2012, 10:49:20 PM
ANY up/down movement in big end of rod is a no-no and will need to be rebuild.
Post by: Stusmoke on June 25, 2012, 02:37:45 AM
Heaps of guys on there are reporting similar problems and saying its normal. the piston can't move around in the cylinder at all either so I'd be willing to bet the rattling noise is coming from the loose conrod. Theres no up or down movement but that massive side to side play has me worried. Also I should add for a piston that was small enough to cause piston slap? It was nigh on impossible to get it back into the cylinder. I don't think the pistons the problem anymore, I think that conrod's side to side play is causing the noise now. I really don't think its meant to be that loose. But I've been wrong before. Also, I'm going to check over the entire bike and make sure theres nothing on there that could be loose and causing the rattle.
Post by: Jeram on June 25, 2012, 03:53:48 AM
0.5mm movement of either side of rid is OK
have you considered that the noise, if not coming from the piston/bore is more likely comming from the crank bearings or the powervalve flutter? RC valves are known to flutter on some bikes and it sounds just like piston slap
Post by: Stusmoke on June 25, 2012, 04:23:58 AM
Post by: Super Trucker on June 25, 2012, 05:10:59 AM
when I did the top end on my 2002 Honda CR125 this past November I ordered the "A" piston for mine to go with the "A" cylinder when the parts arrived I had a "B" piston and a note from the factory stating that you can NOW use the "B" piston in the A cylinder Honda discovered that the tolerances were much closer and could use the B piston with A cylinder without any problems as far as any other years useing those two together I couldn't tell you. Honda pistons are for break in purposes only OOOMMMGGG thats a good one super trucker who told you that BS your pro racing buddies and there mechanics and team managers??That,s the word right from DGY, on some cr125 another year cr piston works better, other manufacters pistons also, especially for expert level mod engines. Yeah honda just figured it out, that you can use the wrong size piston, whatever man. Let,s just try to help Stu out, or you can throw more insults my way, I don,t care.
Post by: Stusmoke on June 25, 2012, 05:24:56 AM
when I did the top end on my 2002 Honda CR125 this past November I ordered the "A" piston for mine to go with the "A" cylinder when the parts arrived I had a "B" piston and a note from the factory stating that you can NOW use the "B" piston in the A cylinder Honda discovered that the tolerances were much closer and could use the B piston with A cylinder without any problems as far as any other years useing those two together I couldn't tell you. Honda pistons are for break in purposes only OOOMMMGGG thats a good one super trucker who told you that BS your pro racing buddies and there mechanics and team managers??That,s the word right from DGY, on some cr125 another year cr piston works better, other manufacters pistons also, especially for expert level mod engines. Yeah honda just figured it out, that you can use the wrong size piston, whatever man. Let,s just try to help Stu out, or you can throw more insults my way, I don,t care.
Agreed. If either of you feel the need to trade barbs please take it off my thread. Not upping either of you just saying please don't bother here. I want to get this sorted and back on the rev limiter.
Ok. My current status is: Con rod says B, piston is a vertex and has 1001 on it. Piston was also damned hard to get back into the cylinder. Theres a notch in the slot for the ring. My question is, is that notch where the ring gap is meant to be? Cos I've found my problem if the answer is yes. Numb skull didn't have it anywhere near there. My current shopping list at Rockymountain stands at:
All the seals, gaskets, separators and oil seals that were listed for the water pump (They didn't have a kit for it), base and head gaskets and a manual. I really don't think the piston is to blame anymore, it has absolutely no budge whatsoever when inside the cylinder and moves through its strokes well without a hitch. I think the rattling noise could be coming from the side to side play in the conrod maybe. Or maybe as Jeram pointed out, the powervalve.
Will I need any specific tools for inspecting the powervalve? Also whats the best way of going about it? Cheers
Post by: 2T Institute on June 26, 2012, 12:24:39 AM
Ok. My current status is: Con rod says B, piston is a vertex and has 1001 on it. Piston was also damned hard to get back into the cylinder. Theres a notch in the slot for the ring. My question is, is that notch where the ring gap is meant to be? Cos I've found my problem if the answer is yes. Numb skull didn't have it anywhere near there. My current shopping list at Rockymountain stands at:
All the seals, gaskets, separators and oil seals that were listed for the water pump (They didn't have a kit for it), base and head gaskets and a manual. I really don't think the piston is to blame anymore, it has absolutely no budge whatsoever when inside the cylinder and moves through its strokes well without a hitch. I think the rattling noise could be coming from the side to side play in the conrod maybe.
Looking at your youtube video I don't think your in any position to judge anyones engine building. The video sowed completely normal side clearence on big and little ends. Ever consider the ring moved in the groove while you were banging it around? Piston sows no sign of hitting the head, so unless the crank mains ave movement, would be easy to think this 'noise' is the sound of a CR125
Post by: Stusmoke on June 26, 2012, 01:09:05 AM
Ok. My current status is: Con rod says B, piston is a vertex and has 1001 on it. Piston was also damned hard to get back into the cylinder. Theres a notch in the slot for the ring. My question is, is that notch where the ring gap is meant to be? Cos I've found my problem if the answer is yes. Numb skull didn't have it anywhere near there. My current shopping list at Rockymountain stands at:
All the seals, gaskets, separators and oil seals that were listed for the water pump (They didn't have a kit for it), base and head gaskets and a manual. I really don't think the piston is to blame anymore, it has absolutely no budge whatsoever when inside the cylinder and moves through its strokes well without a hitch. I think the rattling noise could be coming from the side to side play in the conrod maybe.
Looking at your youtube video I don't think your in any position to judge anyones engine building. The video sowed completely normal side clearence on big and little ends. Ever consider the ring moved in the groove while you were banging it around? Piston sows no sign of hitting the head, so unless the crank mains ave movement, would be easy to think this 'noise' is the sound of a CR125
No I definitely checked everything BEFORE I moved anything around. The ring was definitely out of place and it is most definitely NOT the sound of a 125 engine. The wristpin was out of place, the big end of the rod was moving around both up down and side to side, its hard to see in that vid though. Everything is hard to see I had auto focus off on my phone. Also, to clarify the wristpin bearing is mean to slot inside the small end of the conrod right? Cos I can't see one there. I could be wrong though it was just something I noticed. Oh and theres also scoring on the crankshaft.
I know there is meant to be a tiny bit of side to side play in the big end, theres a little bit too much for my tastes. And also, the small end moves freely from side to side on the wristpin. I'm over it though, if it hasn't grenaded by now its unlikely that it will. Definitely need to do those waterpump seals though.
Post by: Jeram on June 26, 2012, 01:37:09 AM
just lockwire it open or shut the next time your ride the bike and see if the noise still exists. if this is the cause of the noise just make sure the cables are adjusted properly and then if the noise is still there just put up with it as its not doing any harm
side to side movement in the small end is purely based on the movement in the big end. ie: it is free to move as much as it likes but is limited by the big end crank washers
Post by: Stusmoke on June 26, 2012, 03:11:23 AM
powervalve is a simple test,
just lockwire it open or shut the next time your ride the bike and see if the noise still exists. if this is the cause of the noise just make sure the cables are adjusted properly and then if the noise is still there just put up with it as its not doing any harm
side to side movement in the small end is purely based on the movement in the big end. ie: it is free to move as much as it likes but is limited by the big end crank washers
Alright if you're sure. I kinda wish I had thought of that test for the powervalve though
When I tore it down I first noticed those scratches on the crank and the up/down play of the conrod. aswell as the side to side play. I knew immediately that the piston can hardly move side to side while its in the cylinder though I'm not quite that retarded even though nothing seemed to be wrong, besides that ring being out of place I'm still happy that I tore it down, never know what numb skulls like the previous owner do to their bikes. Oh and when I tore the engine down there was practically no coolant in it, so I texted him asking if he had coolant and he said no... Yes... No. Thats right. No wonder it was running so goddamn hot its a miracle it didn't seize.Thanks for the help guys. Ordering in my stuff now and I take a pic of the finished product too.
Post by: Jeram on June 26, 2012, 08:17:50 AM
Post by: Stusmoke on June 26, 2012, 09:02:47 AM
oh and when you lockwire it open, be sure to disconnect what ever it is that drives the powervalve, (gear, cable, shaft ect)
I'm sure you're unsuprised when I say this but I probably wouldn't have done that
Cheers mate
Post by: 2T Institute on June 27, 2012, 02:16:37 PM
No I definitely checked everything BEFORE I moved anything around. The ring was definitely out of place and it is most definitely NOT the sound of a 125 engine. The wristpin was out of place, the big end of the rod was moving around both up down and side to side, its hard to see in that vid though. Everything is hard to see I had auto focus off on my phone. Also, to clarify the wristpin bearing is mean to slot inside the small end of the conrod right? Cos I can't see one there. I could be wrong though it was just something I noticed. Oh and theres also scoring on the crankshaft.
I know there is meant to be a tiny bit of side to side play in the big end, theres a little bit too much for my tastes. And also, the small end moves freely from side to side on the wristpin. I'm over it though, if it hasn't grenaded by now its unlikely that it will. Definitely need to do those waterpump seals though.
If the ring was not in the groove the engine would not run or even turn over. How on earth was the gudgeon pin 'out of place' ?
The small end SHOULD move side to side. Again , your looking at things that are entirely normal.
Post by: Jeram on June 28, 2012, 01:07:52 AM
the only way the gudgeon could be out of place would be if a c-clip was missing? even then aslong as it wasnt destroying your cylinder it shouldnt be making any sound.
If your worried about the crank, just split the cases and have it rebuilt, its not expensive.
Post by: Stusmoke on June 28, 2012, 02:02:57 AM
if the small end bearing was missing, the motor would have lasted less than a few seconds before the rod lets go.
the only way the gudgeon could be out of place would be if a c-clip was missing? even then aslong as it wasnt destroying your cylinder it shouldnt be making any sound.
If your worried about the crank, just split the cases and have it rebuilt, its not expensive.
This whole engine just looks dodgey but if you guys are sure, I drop my case.
No I definitely checked everything BEFORE I moved anything around. The ring was definitely out of place and it is most definitely NOT the sound of a 125 engine. The wristpin was out of place, the big end of the rod was moving around both up down and side to side, its hard to see in that vid though. Everything is hard to see I had auto focus off on my phone. Also, to clarify the wristpin bearing is mean to slot inside the small end of the conrod right? Cos I can't see one there. I could be wrong though it was just something I noticed. Oh and theres also scoring on the crankshaft.
I know there is meant to be a tiny bit of side to side play in the big end, theres a little bit too much for my tastes. And also, the small end moves freely from side to side on the wristpin. I'm over it though, if it hasn't grenaded by now its unlikely that it will. Definitely need to do those waterpump seals though.
If the ring was not in the groove the engine would not run or even turn over. How on earth was the gudgeon pin 'out of place' ?
The small end SHOULD move side to side. Again , your looking at things that are entirely normal.
Okay, I've got the good graces to accept when I'm wrong. I'm wrong. If you're sure its normal I'm sweet with it. The whole ting looks dodgey to me, but to be fair this is the first time I've ever taken the jug off a bike. Well besides that fooper that I used to familiarize myself with how a four joke went together. Oh and just to clarify I meant to gap in the ring on that little upwards grove on the piston. not that the whole ring was out of the grove lol. Not quite that stupid.