classic motorcycle forum
Motorcycle Discussions => British Bikes => Topic started by: raptorkev on February 15, 2011, 07:57:25 PM
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when at around 3000 rpm and engine not under any load an hear metalicrattle open the throtle a touch and it goes engine does not smoke or use any oil
i checked the valve clearances and all fine but did notice yuo could push the rocker to and fro quite easey could it be this
any ideas :-\
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Before you pull anything apart, check carby slide wear!
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Before you pull anything apart, check carby slide wear!
forgot to mention new carbs
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sounds very much like a problem i had , turned out to be both inner valve springs on the inlet side had broken , never had this problem before or since but was told this is common on some Triumphs , mine was fitted with E3134 cams , mushroom tappet adjusters , and R followers if that makes a differance . went well
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sounds very much like a problem i had , turned out to be both inner valve springs on the inlet side had broken , never had this problem before or since but was told this is common on some Triumphs , mine was fitted with E3134 cams , mushroom tappet adjusters , and R followers if that makes a differance . went well
looks like the heads coming off then ???
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Then take the block off and check the little end bushes.
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there were no little end bushes on mine , what year is the bike
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If this model doesn't have bushes then lets all hope the little ends are not worn.
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Well, yeah, but if the bushes were worn he'd be stripping the engine to fit and ream new ones, and if the rods are "bushless" he'll still be stripping the engine to get bushes fitted. Pain in the wossname either way, really.
{I know some people say small end bushes can be fitted and reamed in situ, but I'd rather do it properly on the bench}
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this is a job which can be done in situe . by turning up a suitable guide / mandrel and useing a adjustable reamer ( where are you as i have these tools already ) , you can use each rod eye in turn as a guide and from experience i know this method works well , it also means no bottom end strip down , pack the crank case mouths well , i think you will find there are no bushes fitted and i do not think this is the problem but would be interested to know what you discover . PS just remove the rocker boxes in order to see if you have a spring gone
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If you have not started stripping it yet you could try using a hearth poker or large screwdriver like a stethoscope to try and determine were the noise is coming from. :o
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If you have not started stripping it yet you could try using a hearth poker or large screwdriver like a stethoscope to try and determine were the noise is coming from. :o
thanks guys its a 65 unit motor ive tryed running the motor at stand still but dont seem to able to make it make the noise i am in plymouth soon as i get time will remove rockerboxes and check springs and hope this is the problem anyone tryed renewing springs without taking the head off ?
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It's one of those jobs where it takes longer trying to avoid doing the job properly than it saves. It's only an easy morning's work to remove/replace the head, and grind in the valves while you're in there.
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no bushes fitted to these rods ( and its not a retro fit job ) , changing springs with out taking the head off , ive heard can be done but sounded like to much of a risk packing the chamber with greese and rag with piston at tdc , why bother its easy to remove the head , are you sure this noise is from the motor , has the engine been reboared and are the pistons new ?
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any chance it might be preignition
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piston slap
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piston slap
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ok took head off bores look good pistons marked on tops 70.9488/20 ? there are some other marks but cant make them out theres no small end play no ridge or scores in barrels when pistons on top of stroke in bores i could move them a little bit.the rihgthand piston a bit more than the left.
no broken valve springs and no play in valve guides
the rockers do move from side to side quite easy maybe the springs are a bit weak i have heard of taking them out and just spacing out with washers anyone done this?
would piston slap only be evident when cold ?
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Piston slap is a distinct possibility. . All to often when an engine is rebuilt, the cylinders and pistons are not measured to insure they fit properly. A good clue is to look at the ridge on the top of the cylinder where the top ring stops. If the ridge is very pronounced, that indicates a lot of wear on the cylinder wall and should definitely be measured. If the ridge is there but not very pronounced, then there has been little wear and the old pistons can be reused without a problem. A piston slap noise would tend to be loudest when the engine is cold and disappear.
cut and pasted cos it takes to long to type/
your pistons sem to be original triumph +20
measure everything, it wouldnt be the first time I seen +20 pistons in a 30 thou bore
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Maybe a bit late now the engine is down, but did any experienced mechanic listen to this noise? Sometimes little noises which appear at certain revs can be no more than vibration/resonance and nothing to worry about....
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Back in 1966 I got a new 66 bonnie had to go back to meriden, when they stripped the head it was a valve guide going up and down in the head, then it would stop for a while, had a great day out at meriden tho looked after us well.. ;D
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check piston in each bore and you should have a 4-5 thou gap from front to back. If it is more then piston slap is possible Try each ring in correct bore and you should have between 10-14 thou gap. Remember that the pistons are slightly oval. When putting the rings in the bore use the piston to make the rings level.
I have just done a rebore on my t120
Hope this helps
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thanks guys it looks like it must be a bit of slap pity because it runs well all back together now will start saving for a morgo kit :D
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ok this is taking over my life had it reboard and new pistons run it in guess what still got it its definatly in th top end could it be the rockers moving side to side on the shafts ??? there is not a lot of resistance ie could the springs be weak i think ive read somewhere that you can do away with these springs and put in solid spacers does anyone know about this ???
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You're thinking of the Thackeray washers......but just thinking of a cause then paying money for a fix isn't the way to go, unless you like wasting money, that is.
Said it before in this thread...let a Triumph mechanic (or owner, at least) have a listen. It could be nothing to worry about.
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;D hi guys just thought i would update found the cause and fixed my rattle noise turned out to be backlash on the inner clutch drum and clutch hub its caused me some sleepless nights but got there in the end thanks for all your input :) :) :) :) :)
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did you only have this noise when the cluch was pulled in then ? how did you fix this ? rebuild the hub , im just interested
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only had it when riding about 3000 rpm with no load on the motor fixed with new hub and new inner drum no radial play no noise
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thanks , so where the rollers run was worn , thats the first time ive heard of that one making a noise and one to remember thanks
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the bit with the splines on goes into the spider