Goat Posted July 27, 2014 Author Share Posted July 27, 2014 Hehe, yeah, would probably go for big bore kit if i were to pull it. Though it soon starts to add up. As i would need a new timing chain. And a cam regrind. Then bigger carbs. Then a new clutch. The list will go on.... This is definitely on the cards though. Has been planning on that kit for ages. Just not now as i have too many projects on the go with the Z and the H1. Re sound in that video. -Nah, it dunst sound like that.. Its definitely not a metal on metal sound. Its an air being forced under pressure sound. And its coming out of the right most carb. (up until last Sunday all the test runs i have done have been sweet, not making this sound) I put new plugs in it then shortly after it started making this sound out of right most carb. It kinda is like the sound of running an engine with the spark plug out. puff puff puff puff etc out the carb trumpet. You can feel it really noticeably when hand is in front of carb. It gets louder with revs. Ear hurtingly loud above 6k. Manu - It has the small thread spark plug holes. And my compression tester doesn't fit... 2 Quote Link to comment Share on other sites More sharing options...
Beaver Posted July 27, 2014 Share Posted July 27, 2014 I has compression tester if you need one. Last week before Im far more than a merry walk away so make the most of it! Quote Link to comment Share on other sites More sharing options...
BlownCorona Posted July 27, 2014 Share Posted July 27, 2014 Is there such an occurrence as a valve spring going soft or something? Maybe it really is slow to close the valve. Quote Link to comment Share on other sites More sharing options...
Goat Posted July 27, 2014 Author Share Posted July 27, 2014 It could be a bit tight in its stem seal or something. Cranking engine over by hand and watching the rocker. The valve does open and close, and when its closed there is a "feeler gauge" worth of play. I wouldn't have thought this would indicate that the valve isn't closing properly cos its certainly not a cock in a sock. It will probably only need to be the tiniest bit open for compression to escape. So maby a bit of carbon or something has got stuck in the valve seat an is keeping it open a fraction of a mil. Wish this was 2 stroke. Head off would be a 30sec job... hah Quote Link to comment Share on other sites More sharing options...
thegreatestben Posted July 27, 2014 Share Posted July 27, 2014 Wouldn't be having valve problems in a 2 stroke. You'd be having all sorts of other problems instead. 2 Quote Link to comment Share on other sites More sharing options...
Steelies Posted July 27, 2014 Share Posted July 27, 2014 flogged valve guide/stem seal/whatever stops the magic escaping round there? Quote Link to comment Share on other sites More sharing options...
Rookie Posted July 27, 2014 Share Posted July 27, 2014 Don't worry Joe, these things are easy to pull apart. You could have it done in half a day. Quote Link to comment Share on other sites More sharing options...
Goat Posted July 27, 2014 Author Share Posted July 27, 2014 Could be manu, I do have a couple of spare heads in stock. Will Strip and clean one of them. Get a gasket kit and get some new stem seals then swap em over. Dave - Yea, the do look pretty simple. Should be able to do it in a weekend. 4 strokes are a different realm for me. Should be sweet though, as long as i don't drop the cam chain down into the crank case... Is it simple to time cam up etc? Are there easy to follow marking? Quote Link to comment Share on other sites More sharing options...
Rookie Posted July 27, 2014 Share Posted July 27, 2014 Yea man, super easy, my motor is basically the centre 2 cylinders of yours. The cam chain should probably be replaced while you are at it as they are a pus design, but they are cheap, like $20. there is a mark on the cam sprocket which needs to be horizontal when the alternator is lined up to LT or something. Quote Link to comment Share on other sites More sharing options...
Goat Posted July 27, 2014 Author Share Posted July 27, 2014 Rad, Where did you get cam chain from? Found em overseas. But not keen for international shipping. My tentioner is probably ham aswell. And if i'm doing all this i may aswell biff a 466 kit in.... hah The cases would need to be split for camchain eh? Quote Link to comment Share on other sites More sharing options...
Rookie Posted July 27, 2014 Share Posted July 27, 2014 I just got mine from the local Honda dealer. It was super easy, cut a link out, use a bit of welding wire to attach new chain to old one, and then wind it through, discard old chain and rivet new chain together. Didn't even have to lift the barrels. Definitely helps to have a mate on hand for the riveting process though. Quote Link to comment Share on other sites More sharing options...
CaMpylobacter Posted July 29, 2014 Share Posted July 29, 2014 have you run it and squirted a wee bit of CRC straight into the carb to loosen anything on the valve seat? worth a try. running open stz it could be the back end of a honeybee ruining your shit. Quote Link to comment Share on other sites More sharing options...
Goat Posted July 29, 2014 Author Share Posted July 29, 2014 Thats a splendid idea bei. Probably a spider or something stuck in the valve. As it happened after a few days after getting it running. Went to start it up one sunday evening. Went sweet for a min. Then started making that noise. Will try that tonight. Choice Quote Link to comment Share on other sites More sharing options...
KIRK Posted July 29, 2014 Share Posted July 29, 2014 Bloody gremlins Pour some motorup init Quote Link to comment Share on other sites More sharing options...
CaMpylobacter Posted July 29, 2014 Share Posted July 29, 2014 banana down the cabr at 9500rpms but yeah, if I was me I'd jsut hold it at like 4k and spray a tin of it down the guts to see whats up Quote Link to comment Share on other sites More sharing options...
Goat Posted July 30, 2014 Author Share Posted July 30, 2014 I swapped the carbs over tonight.The old carbs that were on the bike had 98 jets and the factory jets are 75.Anyway, put the old carbs on, bike ran alot better but still had this issue with number 1 cyl. So i decided to pull the head off to check. Excuse the super crap pics, With old carbs on. Just about to pull down. Breather and rocker covers off: Cam out, with a shoelace to stop tensioner from falling down into motor Head off: The 98 jet in the carbs that were on it are WAY too rich!!!. This is the offending cylinder. Nothing obvious until i take the valve out and have a look: You can see how sooty all the cylinders are: The bores still have the hone marks. Except they have major carbon lip on the top (where the piston doesnt wipe): Its the same on all the bores: Ok. So i will pull the head apart, give it a good clean and lap the valves. What would be the best way combustion chambers a good clean. What do you more experienced engine builders think i should do about the bores? Is it fine to put together as is? At this stage i am pretty keen to just spend the minimal to get it going. All the cam chain and tensioners are in pretty good nick. Engine isn't smokey so rings and valve stems are sweet. I just want to get it running for summer! Maby next winter i will pull down again and do a cam and a 466cc kit. And get Voldo to work his magic on the head etc. But for now. I just want a wof and to be able to ride it over summer. Any advice would be most awesome. Chair 3 Quote Link to comment Share on other sites More sharing options...
KKtrips Posted July 30, 2014 Share Posted July 30, 2014 Did you do a compression or cylinder leakage test? Quote Link to comment Share on other sites More sharing options...
Goat Posted July 30, 2014 Author Share Posted July 30, 2014 Naye bae. Probably should have. But didn't have the correct tool and it was too rainy to grab beavers. Also wanted to pull head as i've never pulled down a 4 stroke. (Villiers 4 stroke don't count) Its all learnding. Hah. Will be fun to prep head and put back on. Also needed a new head gasket as current one weeps oil from one of the gallerys. 1 Quote Link to comment Share on other sites More sharing options...
Goat Posted July 30, 2014 Author Share Posted July 30, 2014 I am 99% sure it is a leaking inlet valve. As with the old carbs on, It was spraying fuel vapout about 30cm out the carb at 6grand. And only the one carb. The others were sweet. There are patches of 1mm of carbon buildup on the combustion chambers and on the valves. Poor engine. Those jets in the old carbs were WAY too rich. You can break the carbon off. So im sure a bit has broken off and has gone under the valve seat and is stopping it from sealing. I home the valve seat isn't damaged... This pulldown and new gaskets etc is a perfect excuse to put on my polished side covers Too. Might pull the barrels off aswell and give them a super clean. As they look like they're painted black (they're not. they're just really dirty) Got one of these on the way. 1 Quote Link to comment Share on other sites More sharing options...
Rookie Posted July 30, 2014 Share Posted July 30, 2014 Good shit Joe, it will be back running in no time. Quote Link to comment Share on other sites More sharing options...
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