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Hi Fellas,

I had a lot of problems with my Rickman Metisse last year so in November I sent the bottom end to SRM in wales and this turned up this week.

I got new oversized pistons and have now delivered the devimead barrel to my local engineer shop for a bore and hone.

I have built many 2 stroke engines before, but never a 4 stroke, so I have lots of questions comming and thought I would keep it all tidy in this thread.

I bought a Thunderbolt head from ebay and it was a real mess. I decided to swap out the Lightning head to thunderbolt because I belive that Rickman scramblers came with a T-bolt head from Rickman as standard and It should give me a little more torque.





The head has been welded, faced, fins and threads all repared. Ohh... Big valves and ported to lower the comp a little for modern (crap) fuel. All to help this baby start a little easier.









New spitfire cam, SRM Rods, sludge trap cleaned and dynamic balancing. Engine case repairs include gasket and bearing faces and of corse the singing and dancing end feed and needle bearing conversion. The side cases were blasted, dechromed and then polished. This motor was crinkel painted black when I sent it to SRM.













The cylinder should be back with me in about 10 days.

I will need some assistance on some proberbly pretty basic info, like push rod order, clutch rebuild and the odd niggle that might crop up.

I am hoping to take the bike to a local bike show in April.

At the moment we have 1.5 meters of snow and today it was -12c in my garage (-32 effective outside! ) so hope it warms up a little when I get the barrel back.

First job is fitting the gearbox and new bearings and seals which I wont recieve until next week anyway.

Nice to see.......even better to open.
What size final drive, my big bore runs a 21 tooth without any issues at all.
I was just about to advertise a set of those pistons as I had to go larger again.

Yeah, I`m running 21-47

Pistons are 79.5.

That's the size.
I had to go to 80, but I already had the 79.5 purchased, my mistake. I have two sets of jugs might see if I can sleeve one but I don't think there's enough meat to be able

A tasty package.
First off , cover the quill oil feed with the timing chest, its delicate and get knocked eccentric easily.
There is a critical dimension to check for the head with the new inlet valve, its valve spring end tip to alloy at spring seat, the big inlet valve can sit to proud if the seats are not cut deep enough , causing piston clash. Will dig through my notes for this.

push rods are easy, short ones ( inlets) go to outer cam lobes,

Clutch , strip the centre hub right down, drill out the pop marks on the screws first, look for wear at spider and endplate. replace cush rubbers if wear is light, otherwise a whole new centre is the easiest fix.

gearbox, shim to layshaft DS end, look for 0.003" end float. test assemble cluster in cases, pull /push llayshaft end, 3 thou is just perceptible, any more , clunk or click needs a thicker shim.

Cool.

I have new cush drive rubbers lying around somewhere but didn`t get round to trying to swap them out after seeing what a ballsache it can be and sort of forgot about that......

I wasn`t aware that I could buy a complete cush drive assy, so thanks for the tip on that. I have a couple of mates that have complete SRM clutch but what is the advantage over a well maintained standard clutch?

I have an alli pressure plate that came with the bike.

The SRM clutch will be the 7 plate conversion and the lifting plate, good mods but if you really want to improve it, around 500GBP will get you a Bob Newby belt drive, the plus side apart from running without oil is that you will never need to look at it again.

Gavin, they look like later 40mm valves to me (not the 43.5mm), If you use the bike in the intentions a metise was made for then I'd have suggested lower gearing and advancing the camshaft position by 1 tooth. It would give a lot of bottom end and still pull the ton... I am guessing though that your using it on the road?

if the stock 3 spring clutch has decent flat plates and a fresh centre it just about copes without cranking the springs in too tight.
New clutch centres are ~£100, just get one , odds are the old one is well worn. Un notched fresh splines and no wear on the end plate helps a whole lot.

Seven plate kits are available again another £ton, havnt heard a bad thing about them, one just came in the post for my bike today, the friction plates are thinner by about 40 thou each ( .110" versus .154" for the 6 plate) so the stack height ends up the same, these work with 650 springs , folk that fit them get a good light non slippy clutch. 6 plate stack (6 x150) + (6 x 80) =900 + 480 = 1.380 " , 7 plate stack ( 7 x110) + (6x80) +75 ( new plain) = 770+555 = 1.325, thinner!, good , because its tight in there. the only down side I see is the low fat friction material, theres not much to wear away to FA.
Most important to check your flat steel plates, any warp is a fail, test by putting on a dead flat surface then go round with a 2 thou feeler.

Inlet valve crit dimension, from spring seat base bare alloy to valve tip, should be 1.730" - 1.750", more is OK, shorter means it might say hello to the piston and be coil bound, my head had to go back to SRM to be corrected, hopefully they got it right for you , I found out when it was being checked for valve timing so no harm done.
if you got new springs to match your valves from SRM you will find they dont match the book dimensions, make a note in case you check them later and think they have grown/ shrunk if compared to book values. they work fine, nothing to worry about, I called Geoff when I measured them and the dims were different , he explained that the new spec springs are not the same but work fine.

You pretty much went all out with this engine, looks nice.

Thanks so far fella's....

Apart from SRM, who makes complete clutches (good)?
I'm not really sold on belt drive and I prefer to buy from Europe from a real dealer who deduct vat before sending to Norway.

The Bob Newby whilst being a belt (I think he does a chain version too) is a different belt To that used by the Tony Hayward clutches etc. I did a lot of searching when I went for mine, in the end I found guys like Push Rod Tom uses them on his bikes and decided to go the same route, the bike sees some
Hammer and hasn’t let me down yet, and whilst being a 6 spring clutch is still quite light. 2 friends have since fitted them and more than happy with them. I’m not on some kind of kick back for these by the way, but put a lot of mileage on my bikes and prefer to have something reliable that I can fit and forget. I also change gearbox sprocket sizes quickly also.

Norman Hyde for 7 plate clutch kit, the one I just got from grins triumphs is branded " Aerco". Plenty folk selling these kits in the UK, probably in Europe too.
Burtons ( BBB) sell complete clutches,regular or with an alloy plate option , not heard anything good about the alloy basket.
possibly a few others , its the same clutch parts as a triumph 650/750 twin apart from the triplex basket so a few options exist, but if you are changing the whole thing, new basket means new chain and front sprocket , fitting old to new is not a good idea.

I have bought a new primary and drive chain and full set of sprockets so that's why I'm thinking that now is actually the cheapest time for me just to plump for a complete new clutch

I am warming up to a newby but I'm a little concerned that my rotor won't work on it though. I'm running an electrex word 12v kit and having to fit another ignition would seriously bump up the price, especially now that it would make my triplex chain and front sprocket redundant.

Back and forth, back and forth.....

So, Realy my best/cheepest option is a new cush drive, springs and a 7 plate conversion?

You have new chain and sprocket , then it makes sound economic sense to fit a new clutch basket, you may be able to get an option for a whole clutch without plates , if you want to fit the seven plate upgrade, Whatever way you cut it a whole new clutch will be approx £300, new plain steels are usually a good idea, once the cush centre wears and slip is induced the plain steels warp with heat.
. if you already have the alloy pressure plate then buying separate centre and basket may make sense, tough call. I am envious of the Bob Newby set up, however it comes with its own issues, the primary case needs moved out, and ventilation is a good idea, dry belts need cold air, , on an off road bike which might end up lying in a watery puddle , maybe not such a good thing.

Sorted.

I found a basket from a nos parts dealer, here in Norway.

Ended up with the 7 plate conversion kit from BBB, new rollers , center and SRM pressure plate kit.

But like you pointed out Gavin, I should have just gone for the whole clutch with 7 plate conv. for what turned out to be the same price.

haha.

I have also belt envy but it does seem its not without some niggles. Even more so If I had to shell out for a new 12v system

Manx, can you post a photo of how your ignition should look when fitted?

for the standard alternator the Newby comes with the correct spacing to move everything outboard slightly. Can't see why it wouldn't work here also.

RE the alloy basket, I found the one I had to be very good and strong, My problems stemmed from the clutch centre and primary chain but the basket showed very little wear on the teeth or the tacks the plates run in.

The rotor sits on a washer and cone, up against the sprocket.





It might have been doable by just using a fatter washer?

I decided to upgrade the clutch a little and I am waiting for new gearbox bearings.

Motor is in the frame now at least.



I bought a new clutch basket and cushdrive, new springs, SRM pressure plate and a 7 plate conversion kit.

While I am waiting for parts I think I will start on the top end.

I know this has been done to death and Iv`e read quite a few threads on the subject but I am still non the wiser.

I have first oversize 79.5 pistons, what should my piston to bore clearence be? I have read that clearence should be bigger on lager bore but a concrete number would help more.

Also what should the ring gap be?

Cheers,
Rob

If you bought the pistons from SRM , better ask them,this clearance depends on the alloy mix used in the pistons ( Low ex silicon alloy can be a little tighter) my old iron barrels were 0.0045" clearance when rebored.
Ring gap, book says 0.008" - 0.013", I use 9 top, 12 middle , 9 oil ring, a wider gapped 2nd ring is meant to help seal better, better loose than tight here.
Important to get bores finish honed with a 150 -180 grit hone, this is a lot ruffer than most modern stuff, make sure the reborer uses this or suffer poorly seated rings.
This comes up a lot , google "britbike forum bore honing" or such like and read what John Healy says about it.,

My head was the same, I spent ages de masking, removing the step around the inlet faces, nerve wrackingly close to the valve seat , dremel and small burr.

What is the advantage of removing the step?

I`m clueless but pretty handy with a dremmel on 2 stroke ports.

ok, will do!

Clearence recomended by SRM is 0.0045, like you said Gavin.

I came home ready to fire up my dremmel but the dark bits on the head are just dark bits, there is no recess or edge around the valves.

My daughter finaly got her act together and machined me a rear axle, so now its standing on its own two wheels again.

I'm not sure this is the norm on brit bikes but I have done this on my scooter engines for 20 years with great results.
I always buy 2RS (2 rubber seals) bearings if they sit on a seal side of the engine case.
I've never been keen on running sealed bearings in places that get good lubrication so I take out the seal on the lubrication side but keep one in on the seal side and pack the area in between with high temp grease to lube the outer seal.

I have a bit of a fobia against leaks because when you get a top end leak on a 2 stroke, it goes bang very quickly.








One thing I have come to think about is the breather from the primary case.

There is a little hose that sprays oil on the chain and from the chain all over the bike. When I green lane the oil also attracts loads of other crap that also sprays all over the bike.

Is there an simple alternative method for the breather ? I imagine simply blocking it off is a no-no?

Err.. I did a search and it looks like I can just block the chain oiler.

Is that correct?

sorted. thanx

Arrgghhh!

A little hiccup. I got a phone call from the engineering shop today and the bore is seriously worn .

I bought oversize 79.5 pistons and they say that if they bore it to the new pistons the barrel will still be too big at the base and can cause piston slap.

I'm pretty sure I can take the devimead to 80mm but would like this confirmed by someone in the know please.

Can one of you nice chaps point me in the right direction to someone who can sort me out with some quality pistons... preferably in Europe that can deliver fast?

The snow is melting!

Great news. Thanks Nick.

Is there any particular brand og piston that I should be looking for?

Hi

You can get the B44 GPM slipper pistons from Mark Cook at [email protected], Not sure about 80.5mm but certainly 80mm.

regards

John

+1 Although I was certain he was using the JE Pistons... Maybe he has both

I have 80 mm in mine.
Tried the slipper pistons without much success they got pinched up then became noisy.
Maybe not the piston fault

EdV's JE forged pistons are great, plus they come with a modern ring pack and run tight bore clearance. I've seen cheap cast B44 pistons at a higher price. I don't see Ed's pistons as expensive, but they are top shelf. Ed is also great to deal with.

Another thing about Ed's B44pistons is the short skirt, as it keeps the piston completely in the bore at BDC. Or depending on cyl and stroke they stay further up the bore at BDC.

Too big at the base ???? was it running its rings at the bottom of the piston ?

Wak!

That is a very good question, one I can not answer.

I would have thought that if the jugs were worn, that the area that the rings run in would be widest, just like you.

My cylinder shop are also confused but they think its basicly a botch job, maybe a home garage bore?

To sort out the barrel the shop wants £300, and pistons will come to £400 with tax and shipping..... almost enough for me to justify a brand new alluminium barrel..... almost

Two of these would workout much less than 400pound; $380us plus shipping.

https://www.shopevengineering.com/E...182&shopBy=-8415&catalogId=-2087

Wont be a lot less, if I buy stuff from the states to the UK , it almost always comes to the same numbers in pounds as dollars by the time shipping and customs have had their share.

Postage from the states is normaly quite expensive to norway (NON EU).

Norwegian VAT is 25% plus 5% handeling fee and toll.

The kroner is very low at the moment against all currancies but esspecialy the dollar.

Postage from UK normaly quite cheep and the best european dealers deduct VAT so I just have a 6% markup on UK prices after ive payed norwegian VAT.

Ok.

Talked to SRM and they can exchage my oversize pistons for standard (79`s ) and take the price off thier 750 kit, so I will be going down that route.

My wife has thrown all her toys out of the pram, so hope nothing else crops up, or it will be me she is throwing out the house..

I feel you man .

Ok, a couple of days off work and I had to see if my cunning plan would work.

The cunning plan was to hide a panckake filter just in front of air filter box and with a bit of fettleing I got it to sit pretty good.

A problem I can see is that if/when I need to take the the carb off, i`ll be pretty fecked because I don`t have enough wiggle room to take the filter off to be able to move the carb off the studs.

The only (proberbly terrible) solution I can come up with is to fit the 2 to 1 manifold with bolts, rather than studs.





Bolts won`t work on the carb itself because the carb body is in the way.

what do you fellas think? I can cut a hole in the filter box and fit the original type Metisse filter but then I have to find somewhere else for the 12v system and will need to make a new wireing loom.

A Socket head or "allen" bolt will work in lieu of the studs.

Yep.

And the million dollar question is what thread should they be?

Are you thinking carb or manifold?

Is there nor the rudiments of an airbox already , that pancake looks like too hard a puzzle, maybe use the battery box to house a car filter cut to size with a bit of hose from carb to box.

The air filter box is full of electrickery and the battery and I can't really hide it anywhere else.

Difficult to see from the photos how much room there is behind the carb for an air filter, perhaps one solution would be too use a threaded cone filter available from AMAL seeThis Link. This filter is apparently extends beyond the rear edge of the carb by 65mm, you may need to cut away some material from the battery box but as its cone shaped it should be minimal.

Regarding the manifold studs as already mentioned I believe the thread is 1/4 UNF, so it should be possible to use socket caps in place of the studs.

Hmm.. good thinking batman.

Did a bit of measuring and looks like that could work. If I cut a hole just big enough to enable me to take the filter off then I have ample room to take the carb off.

I'll have another look tomorrow.

Right. Clutch time.

I fit my clutch this evening but it looks like my rod has worn short so I had to order a new one.

I also think that my clutch inner cable is too short .

Should the clutch mechanism (later type) be completely relaxed with the cable attached?

I think the cable length has been made shorter to compensate for the worn rod.

And how tight should the springs be? I think I read somewhere that one coil should be visible.
Does that sound right? It's lifting crooked on one spring should that one be backed off a little, or the others tightened?

Proberbly basic stuff for you guys.

The three ball ramp should be fully relaxed with the cable slack ( the 3 mounting screw heads should be visible through the three holes in the moving part), it will "click " loudly if it isnt. Screw the cable adjusters in at each end of the cable,theres about an inch on each one. Use the clutch pressure plate centre adjuster to set the push rod clearance about a 1/4 to 1/2 turn from touching. this beds in fast and closes as the plates settle in , recheck after a few hundred miles. or sooner.

Try setting the clutch springs with the centre stud just flush with the screw slot bottom, fix a pointer up using whatever comes to hand use the casing flange tapped holes to mount a screw with a bit of stiff wire. Spin the clutch withdrawn and tune out wobble by tightening the high spring, or slackening the low side.

A couple of finer points on tweaking the springs, the adjuster screws have a dimple /pip which engages with the end of the spring, when fine tuning bear this in mind, you can feel the pip ride over the spring end as you tighten, 1/2 turn adjustments that dont meet pip to spring end will change in use as it settles in, its better to err on the light side, your left hand and the clutch cable will last longer, you can always tighten up later if you get slip, this will show up in 3rd when tackling hills.
Aim for somewhere like 6 - 10 lbs pull at the hand lever with a spring balance to check .



This works for me with 750 springs. I dont know about the 7 plate set up , but it would be a good starting point, if it slips in use you can tighten them up later.

Shortening the cable to suit a worn rod is a bad idea,

have you got the ball bearing that goes between the end of the pushrod and the 3 ball ramp cup, if it was missing it might account for the pushrod discrepancy?

While you are in there slather the three ball mech with bearing grease , the black stuff with moly in it, then you will know where the black drool is coming from later, wink, it helps keep the clutch light.

Thanks Gavin.

The little ball is there and so is the clicking noise, even with the adjusters fully backed off.

My manual only shows the early type clutch but that has a springy thing between mechanism and cable. Should the late type also have that?

My rod is about half a cm too short and looks cut. Almost looks like some numpty has cut it to compensate for too short inner .

With some of the clutch conversion kits like the SRM pressure plate you had to shorten the rod about that much

I have the SRM pressure plate kit and its still too short.

My cylinder kit is sorted now and will be sent today along with a new clutch rod.

The early type clutch has the springy thing, not yours the cable inner goes straight to the op arm., you need a new cable from the sound of it, either for a 70 or 71, or make your own. its not unusual to cut the push rod in half and add an extra ball bearing, you may get away with that. When cutting push rods, clean up cut on grinder , then heat to cherry red and quench in oil to harden the end.

I make my own cables. I`m trying to find somewhere local that has cable elbows, so I can add one for better pipe clearence at the same time.

Yup, cherry red and quench in oil. will do, cheers.

something to think about , to get the correct push rod length, remember that as the clutch pack wears down, the centre adjuster screw will be backed out, cut pushrod to length so that the centre adjuster is screwed almost flush with the lock nut for the new plate stack. As it wears in this leaves max adjustment.

The female threads into the outer ally case for the cable adjuster boss are 1/2" UNC, ( 13 tpi),, maybe get a small dia tube bend and weld to a drilled 1/2" UNC threaded rod about an inch long with lock nut to fit the casing , the adjuster could go mid cable. When I need stuff like this I go to the dump with a hack saw and an adjustable spanner, rake about in the metal skip for inspiration.

Cables, wires and electrics all sorted.

According to tracking, the rest of the parts should be here by Friday... Not long now.



Hard to see on the pic but I found some flexy heat protective stuff (in metal) I fit to the clutch outer and when you bend it, it stays put. No Idea what its realy for but found it at my local hardware shop.

Could someone post a photo of the correct route for a tbolt rocker feed pipe please?

Ok. Ive got a strange one here...

I`m finnished builing the top end and added oil and currently priming the motor.

When turning the motor over I get a click from the right hand inlet cam follower or cam. the others are silent.

What have I done wrong now?? Its not the tappet because I have taken the rod off the rocker arm to see if I could localise the sound.

A tight cam follower might do this, strip , examine, maybe a burr, dirt ? Remove idler pinion and spin cam with no push rods before pulling the barrels, that should help isolate it.

Ohh jezus..... thats 3 nights work.

Its a real real pain to fit and remove the head becaus there isn`t enough room to lift it without removing the studs.

Join the club , i got the lump in , then found the crank wouldnt turn last rebuild, cocked up the TS bearing spacing, now I just whistle at it and it jumps out ,I wish.

Before I went to bed I span the engine a couple of times on the kick start and it clicks just before the both inlet valves are activated. The cam and shims and bushes are brand new.
The only parts that are re-used are the followers but I inspected them and they didn't look worn and moved fine in the seats.

I also span the motor without the head on and it was silent.

Why would the cam gear click on the 2 outer lobes?

Could it be that the followers dont quite follow the cam?

I used some sticky start up grease to keep the followers in the barrel but maybe that shouldn`t affect it while they are under spring pressure.



Didn`t get any sleep last night.

I`m loading up the video on youtube... comming soon

Here!

As NickL has already mentioned, take a closer look at timing gear backlash as the source of the clicking noise.

I had a similar issue recently on a Triumph engine I built - http://www.britbike.com/forums/ubbthreads.php/topics/728934/re-does-this-sound-right#Post728934. The dry timing gears made a considerable clicking noise, even although the backlash was not excessive. When I applied some oil to the gears, the noise reduced considerably and sounded normal, although I've not actually run the engine yet!

Ahhhh....

I wasn`t ignoring Nick, I just wasn`t sure what he was saying.

The central timing gear went in dry and the sound could come from that area.

What did you oil yours with Bry?

I just squired some 20W/50 engine oil on the idler gear teeth with an oil can to test with the timing cover off.

Ok. Not a big job. I`ll try that tonight.

cheers.

Wow fellas.... I will sleep very well tonight.

Thank you so much!

[video:youtube]https://youtu.be/7QU4n6GictE[/video]

If I told you that the motor was completely quiet after oiling the timing cogs I'm pretty sure you wouldn't belive me!

If I have to remove the inner timing cover again I'm pretty sure I'll remember to empty the gear box next ...

Hahaha

Me too. I was worried that I had done something terribly wrong.

Mocking up exhaust brackets...

So I have booked myself in to a motorcycle show on Saturday, in the riden to the show catogory and I havn`t even fired her up yet!

Made some fittings for the right hand pipe, hopefully do the other side tomorow. Unfortunatly the hole in the frame is in another possition on the left hand side to make room for the rear light switch so I cant just measure the stuff I made tonignt.







I think it will be pretty sturdy when the tie bar is fitted to the headers, Made the bracket out of 3.5mm stainless.

I kicked them up slightly which is how they are fit on a picture I found in the Metisse book. Loads of room for the clutch cable and exhaust is off my leg for when standing on the pegs.

Tonights the night!

Going to (try) and fire her up. I just need petrol...

Wish me luck

Good looking bike, your neighbours will love you for these open exhaust pipes.