Knackered's New Project - Lightly Modded Trail Mk1

Jeram
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Re: Knackered's New Project - Lightly Modded Trail Mk1

Post by Jeram » 07 Mar 2012, 22:24

if you want some real simple engine mods, has anyone tried this on the CRM? because it works on pretty much all two strokes

add a second base gasket to raised the cylinder 0.5mm (can go higher if needed), this increases the port duration (and port time area) which increases top end slightly.
then you just need to machine the surface of the head to bring it down to match the 0.5mm lower piston.

or for more bottom end, do the exact opposite.

:)

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knackeredMk1
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Re: Knackered's New Project - Lightly Modded Trail Mk1

Post by knackeredMk1 » 09 Mar 2012, 17:37

Suprised at the total cost of swingarm and linkage bearing/seals/bushes. I had most of swingarm bits already but the suspension linkage cost >£80 to refit. Bearing suppliers only a few pounds cheaper than Honda, with bushes and one bearing Honda only.

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Re: Knackered's New Project - Lightly Modded Trail Mk1

Post by john7780 » 09 Mar 2012, 18:28

Jeram wrote:if you want some real simple engine mods, has anyone tried this on the CRM? because it works on pretty much all two strokes

add a second base gasket to raised the cylinder 0.5mm (can go higher if needed), this increases the port duration (and port time area) which increases top end slightly.
then you just need to machine the surface of the head to bring it down to match the 0.5mm lower piston.

or for more bottom end, do the exact opposite.

:)
as an example tm's have different thickness base gaskets, i currently run a 2mm as opposed to the 5mm which was on it and boy do you notice the difference, i have one of the few 250 2 smokers you have to kick like a four stroke ( having to lean on something) :lol:
front brakes only slow you down anyway!!!!

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Re: Knackered's New Project - Lightly Modded Trail Mk1

Post by Jeram » 10 Mar 2012, 00:32

hmm a TM, lucky man ;)
Ill be buying one as soon as they put there injection module on the 300s haha

wow, lowered your cylinder by 3mm, that must give it a good bottom end kick!
Im guessing you have a different head insert to make up for the lost compression?

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Re: Knackered's New Project - Lightly Modded Trail Mk1

Post by Jeram » 10 Mar 2012, 02:08

.2mm instead of .5mm ??

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Re: Knackered's New Project - Lightly Modded Trail Mk1

Post by john7780 » 10 Mar 2012, 11:53

the head stays the same its just 'o' rings, the base gaskets are .1 to .5 mm in thickness and yep the bottom end difference is great, its very useful for negotiating enduro tracks ;)
front brakes only slow you down anyway!!!!

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Re: Knackered's New Project - Lightly Modded Trail Mk1

Post by knackeredMk1 » 15 Mar 2012, 20:25

Started rebuild today -

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Re: Knackered's New Project - Lightly Modded Trail Mk1

Post by knackeredMk1 » 16 Mar 2012, 21:29

Water & oil plumbed in. XR250 '95 shock.

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Re: Knackered's New Project - Lightly Modded Trail Mk1

Post by voodookid37 » 17 Mar 2012, 00:18

looking good young man,,, :D
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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Re: Knackered's New Project - Lightly Modded Trail Mk1

Post by Jeram » 17 Mar 2012, 02:42

nice!

although Im sure your already planning to do so, be sure to paint those radiators and give the hoses a clean and soak in wd40 overnight to bring out their lovely shine :)

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Re: Knackered's New Project - Lightly Modded Trail Mk1

Post by knackeredMk1 » 21 Mar 2012, 16:41

Took the loom apart and cut out some unnecessary (sp?) bits. More to go with the leadlight section.

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Re: Knackered's New Project - Lightly Modded Trail Mk1

Post by knackeredMk1 » 21 Mar 2012, 22:18

Decided to fit the original Mk1 engine at the moment. I have got a Mk3 engine that is in really good nick. It's on the original bore with not a scratch on it. My current thinking is to do the Mk3 engine up like I did to my original Mk1 and then put the Mk3 engine in that bike (longer gearing for the road), and move that Mk1 engine into the current project. Might take next Winter to do though :? .

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Re: Knackered's New Project - Lightly Modded Trail Mk1

Post by knackeredMk1 » 24 Mar 2012, 22:28

A little further -

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Re: Knackered's New Project - Lightly Modded Trail Mk1

Post by knackeredMk1 » 26 Mar 2012, 19:09

Silencer - Pro Skill. Stainless steel in and out pipe + new stainless perforated section and repacked.

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Re: Knackered's New Project - Lightly Modded Trail Mk1

Post by back off road » 26 Mar 2012, 22:37

coming together now :D
Im thinking about a bike with more valves than a powervalve


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