Mk1 engine rebuild
Mk1 engine rebuild
Hi folks, I'm looking for some advice regarding an engine build for my Mk1 CRM. Unfortunately after enjoying my Mk1 for most of last summer and a spot of commuting, it seized on me. Luckily my mate was with me so I could get a tow home. I bough the bike through the forum back in April last year.
Link to the build by knackered Mk1- viewtopic.php?f=14&t=7540&p=50511#p50511
To save a bit of time, and for convenience I put the engine into a local restorer for a rebuild but after a lot faffing about he's come back with a quote for 650 to rebuild the engine (it needs a full rebuild inc crank and barrel re-coat). Can anyone give me a rough idea of the cost of parts I should be looking at, as I could do the build myself to save some cash, and also any contacts for a crank rebuild, new con rod and barrel re-coat? Any previous experiences?
Or would I be better looking out for a 2nd hand engine as spares?
Oh, one more question, as a last resort I may break the bike or sell as is, would there be much demand for parts etc.
Sorry for all the questions.
Thanks
Ross
Link to the build by knackered Mk1- viewtopic.php?f=14&t=7540&p=50511#p50511
To save a bit of time, and for convenience I put the engine into a local restorer for a rebuild but after a lot faffing about he's come back with a quote for 650 to rebuild the engine (it needs a full rebuild inc crank and barrel re-coat). Can anyone give me a rough idea of the cost of parts I should be looking at, as I could do the build myself to save some cash, and also any contacts for a crank rebuild, new con rod and barrel re-coat? Any previous experiences?
Or would I be better looking out for a 2nd hand engine as spares?
Oh, one more question, as a last resort I may break the bike or sell as is, would there be much demand for parts etc.
Sorry for all the questions.
Thanks
Ross
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gregorious77
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Re: Mk1 engine rebuild
I thought only the AR has a Nikasil coated barrel but I could be wrong of course.
I would phone http://www.pjme.co.uk/ I have used them for an old RM125 and they were really really good. gave me loads of info and even told me how to set the squish for best power etc.
Rebore, hone and dress ports is £30 plus parts (piston/rings etc) Crank rebuilding is £30+ parts Nikasil coating is £135+VAT
£650 is a bit steep if you ask me although there would be a lot of labour in splitting cases etc.
I would phone http://www.pjme.co.uk/ I have used them for an old RM125 and they were really really good. gave me loads of info and even told me how to set the squish for best power etc.
Rebore, hone and dress ports is £30 plus parts (piston/rings etc) Crank rebuilding is £30+ parts Nikasil coating is £135+VAT
£650 is a bit steep if you ask me although there would be a lot of labour in splitting cases etc.
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knackeredMk1
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Re: Mk1 engine rebuild
Sorry to hear things have gone pear shaped 
.
The engine was rebuilt with new mains under my friend's ownership and had a rebuilt crank and rebore not long before that. I suppose that was all quite a long time ago now though.......
I'm surprised the crank needs doing unless the seizure was oil related or happened at high rpm. Gregarious is correct in that only the AR needs a replated bore. The others just need to be rebored and a larger piston used. If there is horrific damage then it's a new barrel.
A rebore, piston, gasket kit, etc is going to cost £170-200 in parts even if you do the work yourself. By the time you have added crank rebuild, more gaskets, main bearings and labour you will get to ~£650. (~£150 for crank rebuild inc. conrod, £40 in gaskets, £50 main bearings).
If you were closer I'd help with the work............. Unfortunately all I can offer is a very little used Wiseco TRX piston (+2.0 as I remember your current piston is +1.50)) and new little end bearing for £50 inc. postage. New piston and little end ~ £100-120.
.The engine was rebuilt with new mains under my friend's ownership and had a rebuilt crank and rebore not long before that. I suppose that was all quite a long time ago now though.......
I'm surprised the crank needs doing unless the seizure was oil related or happened at high rpm. Gregarious is correct in that only the AR needs a replated bore. The others just need to be rebored and a larger piston used. If there is horrific damage then it's a new barrel.
A rebore, piston, gasket kit, etc is going to cost £170-200 in parts even if you do the work yourself. By the time you have added crank rebuild, more gaskets, main bearings and labour you will get to ~£650. (~£150 for crank rebuild inc. conrod, £40 in gaskets, £50 main bearings).
If you were closer I'd help with the work............. Unfortunately all I can offer is a very little used Wiseco TRX piston (+2.0 as I remember your current piston is +1.50)) and new little end bearing for £50 inc. postage. New piston and little end ~ £100-120.
Re: Mk1 engine rebuild
Thanks for the replies fella's, much appreciated.
The place that has the engine offer the strip/inspection for £60 so I think I may settle up for that and have a go at rebuilding the engine myself. I've done 2 stroke top ends in the past and also a few complete rebuilds on my monkey engines so should be ok with doing it. I'll give PJME a try for some parts costs too.
Steve, thanks for the offer and I may take you up on the piston and little end bearing if I can let you know for sure next weekend, as it'll be Fri before I can get the engine back and have a look at the barrel for myself?
Can you remember the name of the place that rebuilt the crank the last time as the guy who has the engine just now said he could only find one place to do the crank rebuild?
I'm not sure the exact cause of the seizure but I don't think it was oil related. One weird thing was that the spark plug had a hard (almost carbon like) build up across the electrode that was pretty solid, and closed the cap in. I had to give it a good whack to get it to come off?
The place that has the engine offer the strip/inspection for £60 so I think I may settle up for that and have a go at rebuilding the engine myself. I've done 2 stroke top ends in the past and also a few complete rebuilds on my monkey engines so should be ok with doing it. I'll give PJME a try for some parts costs too.
Steve, thanks for the offer and I may take you up on the piston and little end bearing if I can let you know for sure next weekend, as it'll be Fri before I can get the engine back and have a look at the barrel for myself?
Can you remember the name of the place that rebuilt the crank the last time as the guy who has the engine just now said he could only find one place to do the crank rebuild?
I'm not sure the exact cause of the seizure but I don't think it was oil related. One weird thing was that the spark plug had a hard (almost carbon like) build up across the electrode that was pretty solid, and closed the cap in. I had to give it a good whack to get it to come off?
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knackeredMk1
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Re: Mk1 engine rebuild
SEP are the guys I know can do the crank and have been used by LT and others on this site. - http://www.sep-kegworth.co.uk/page1.htm
Let me know about the piston as I'm getting ready another batch to put 'For Sale'.
Not sure about the carbon build up that would suggest that the engine was getting a lot of oil and not running lean
.
If it is just the top end then it is quite simple even if the engine is in pieces but I would change the mains as a matter of course as well. I've got a crank case gasket and a head gasket that would be suitable (what I have been using in over bored MD24 engines) in the 'For sale/wanted' section but all the other gaskets are gone.
Let me know about the piston as I'm getting ready another batch to put 'For Sale'.
Not sure about the carbon build up that would suggest that the engine was getting a lot of oil and not running lean
.If it is just the top end then it is quite simple even if the engine is in pieces but I would change the mains as a matter of course as well. I've got a crank case gasket and a head gasket that would be suitable (what I have been using in over bored MD24 engines) in the 'For sale/wanted' section but all the other gaskets are gone.
Re: Mk1 engine rebuild
Thanks, I'll give them a try once I get the engine back.
Will do, I'm getting the engine on Fri so will let you know next weekend if this would be ok?
Will do, I'm getting the engine on Fri so will let you know next weekend if this would be ok?
Re: Mk1 engine rebuild
Just a quick update, I've almost got the engine back together now and will get everything checked and torqued up this week hopefully.... then get the engine back in the frame in the next couple of weeks when I get a chance. We're renovating our house just now so time/money is at a bit of a premium.