My Mk1 project with Mk2 engine

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mereneil
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My Mk1 project with Mk2 engine

Post by mereneil » 30 Jul 2010, 20:45

A few pics and the story so far.
I bought the bike pretty much as it is. The engine that was fitted has a major big end seizure which has badly scored the crank casings, and on closer inspection actually cracked one of them. However, lucky for me it came with a part stripped MK2 engine in a box. It has a good crank, but does need new main and gearbox bearings / seals. I have stripped it down ready for bearing and seal ID and ordering from my local suppliers. A quick phonecall to LT should sort out a full gasket set and a new set of rings to go with the choice of 2 standard pistons / barrels, which are in good order.

http://i610.photobucket.com/albums/tt18 ... one128.jpg

http://i610.photobucket.com/albums/tt18 ... one130.jpg

http://i610.photobucket.com/albums/tt18 ... one146.jpg

http://i610.photobucket.com/albums/tt18 ... one127.jpg

http://i610.photobucket.com/albums/tt18 ... one145.jpg

http://i610.photobucket.com/albums/tt18 ... one133.jpg

Got my main bearings today. £11 + vat each from Antifriction in Wrexham. Koyo items

This is as far as I have got, but will spend a day on it tomorrow cleaning and getting it ready for the rebuild. Might also buy a honing tool to give the barrels a good freshen up.

Will keep you all posted on my progress. PS I already know about the issues with the timing difference between the Mk1/2 and am quietly confident a small tweek on the cdi pick up point will sort this.

voodookid37
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Re: My Mk1 project with Mk2 engine

Post by voodookid37 » 30 Jul 2010, 22:45

in the same position. mk2.2 into a mk1...however with bits of the mk1 onto the 2.2 engine.
sadly might be a slower build than yours due to work.
will share any oddities .. :D

at the moment it is going to be 2.2 cases, crank and head with mk1 electrics ,clutch ,etc
gaskets all ordered......now just to get that darn clutch off.lol

shame cos the mk1 one engine was sweet until the gearbox exploded.
mk1... with mk2.2 engine,running mk1 electrics,mk1 carb on standard mk1 jetting + settings.dep front pipe.jap alloy can of unknown make. twinair filter on plastic cage.l/h mk1 rad.r/h mk2 (extra coolant takeoff on 2.2 head)
xr650 wheels .gritty front,mitas rear

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knackeredMk1
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Re: My Mk1 project with Mk2 engine

Post by knackeredMk1 » 30 Jul 2010, 22:52

mereneil - Why not just modify the crankcase so the one pickup that is in a different position for the Mk2 (Just needs some spacers), is in the same position for the Mk1 so you can use all the Mk1 electrics and generator rotor :?:

mereneil
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Re: My Mk1 project with Mk2 engine

Post by mereneil » 31 Jul 2010, 09:31

knackeredMk1 wrote:mereneil - Why not just modify the crankcase so the one pickup that is in a different position for the Mk2 (Just needs some spacers), is in the same position for the Mk1 so you can use all the Mk1 electrics and generator rotor :?:
I've not really looked into it in any great depth yet to be honest. I think the only slight snag is the neutral switch which is completely different on the Mk2 and has 3 wires instead of the one. I will have a good search through the forum before I ask the question!
Thanks for all the feedback though, all suggestions are gratefully received

voodookid37 wrote:in the same position. mk2.2 into a mk1...however with bits of the mk1 onto the 2.2 engine.
sadly might be a slower build than yours due to work.
will share any oddities .. :D

at the moment it is going to be 2.2 cases, crank and head with mk1 electrics ,clutch ,etc
gaskets all ordered......now just to get that darn clutch off.lol

shame cos the mk1 one engine was sweet until the gearbox exploded.
I am going to use the bulk of the Mk2 engine too. I will be using existing loom and probably Mk1 stator, rotor, pickup etc. Did you notice the neutral switch difference?
Ah the dreaded clutch nut, it's a pig when the engine is on the bench! With the engine in the upright position, I undo mine by placing a length of flatbar through the outer basket and locating it within one of the inner slots. I then jam it under the end of the crank, making sure that there is pressure on it to keep it in the slot. Get behind the engine (exhaust away from you). Then using a breaker bar and socket (27mm from memory) I undo the nut. You have to counter the front of the engine because it just wants to move with you. A second person is always handy to put weight on the engine for you, but it is manageable on your own.
I know it sounds a bit brutal, but I am a mechanical fitter by trade and I weight up all the risks before I went ahead. 2 engines stripped without a problem so far.

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knackeredMk1
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Re: My Mk1 project with Mk2 engine

Post by knackeredMk1 » 31 Jul 2010, 14:43

If you have 3 wires from the neutral switch you have a Mk3 engine in pieces. No different from Mk2 apart from bolt, instead of nut on the end of the crank, the neutral switch and generator rotor timing.

I think EddieEvans did a swap Mk2 - Mk3 engine and conected all the wires together to get a neutral light working on a Mk2 loom.

mereneil
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Re: My Mk1 project with Mk2 engine

Post by mereneil » 31 Jul 2010, 19:46

:BB
This might be good news for me because the bike and all electrics are mk1, therefore hopefully I can simply put the mk1 rotor, stator and pick up sensor on the Mk3 engine without worrying about the timing difference.
Thankyou knackered, you are obviously a god in the crm world!

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knackeredMk1
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Re: My Mk1 project with Mk2 engine

Post by knackeredMk1 » 31 Jul 2010, 19:57

Thank you though I am sure I don't deserve that accolade.

Just be aware you are working at the limits of the knowledge of this forum. In theory everything stated above is correct but you cannot be certain about what has happened to both these engines.

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Re: My Mk1 project with Mk2 engine

Post by mereneil » 31 Jul 2010, 20:55

Well I will endeavour to get this bike running. I hope some useful info will come out of it. I'll keep you all posted on any problems

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Re: My Mk1 project with Mk2 engine

Post by knackeredMk1 » 05 Aug 2010, 20:47

Mk1 electrics and Mk3 engine should make the best of all worlds as the Mk3 is suposedly physically stronger, wider gear ratios (best for road) with better performance. Whilst the ECU and PV controllers of the Mk1 are virtually bullet proof compared to the Mk2/AR and a lesser extent the Mk3.

When you have finished the engine and got it running come back to me as there is one final little tweek you need to make the best out of the mix.

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Re: My Mk1 project with Mk2 engine

Post by mereneil » 05 Aug 2010, 22:00

That sounds like good news to me Knackered! I have slowly been receiving parts for the rebuild, and busily cleaning bits. I have just agreed to do 2 weeks work in London starting Monday so wont be able to get at it much until I get back.
I will definately be in touch for the tweek you have in mind for me.
Thanks for the encouragement!!

I really like the look of USD forks compared to mine, and might consider trying to sort some out. However, I don't want to make the bike any taller because the current height is spot on for me. Time to find some forks, yokes, front wheel and spindle. Then again I might just wait til its running first!! Its very easy to spend a fortune on a big pile of bits that wont actually move under their own steam!


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