Author Topic: Ace assisting Bullet Whisperer racing effort  (Read 124599 times)

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Bullet Whisperer

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Reply #150 on: July 08, 2014, 10:22:02 pm
After making sure a modification to the rear engine / gearbox mounting involving an Interceptor type bracket on the back of the gearbox all lined up and fitted, the frame, swingarm and new alloy seat unit all went away for painting. I wanted to polish the alloy seat unit, but was outvoted  ::)
 Anyway, what you see below is no longer a mock up [apart from the top end], everything else is going together for keeps. I replaced one broken spoke in the rear wheel and checked and adjusted all the others and put a used racing tyre on, in readiness for running in and dyno testing, which shouldn't be far off now  ;)
 B.W.


ace.cafe

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Reply #151 on: July 09, 2014, 01:14:46 am
That is a VERY exotic bike!
I love it!
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Bullet Whisperer

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Reply #152 on: July 16, 2014, 08:30:23 pm
More news - My Father, Dave is going to the Midlands tomorrow to collect the pistons which have been specially made to our [Ian's] design !!
 The top end assembly work will start on Friday, if all goes to plan.
 Meanwhile, I have fitted the top and bottom yokes and forks to the frame, put a new tyre on the front wheel and the rear wheel is ready, with a used tyre fitted in anticipation of some runs on the dyno, before racing at Darley Moor in just over one week's time, if all goes to plan.
 This machine's stable mate, the 350 Clipper is 'on fire' at the moment, having taken 4th and 2nd places on the Saturday at Lydden Hill a couple of weeks ago and after some adjustments, two wins on the Sunday at that venue, hopefully its' larger sibling will soon be doing likewise  ;)
 B.W.


ERC

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Reply #153 on: July 16, 2014, 08:55:17 pm
VERY impressive. Beautiful job. Was wondering it looks like the stand it's on has no ramp. Do you just pick it off when done.  ERC
2-57 Apaches, 2-57 Trailblazers, 60 Chief, 65 Interceptor, 2004 Bullet, 612 Bullet chopped.


ace.cafe

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Reply #154 on: July 16, 2014, 08:57:07 pm
Absolutely FAB !!

Dying to see/hear the running report!
 ;D
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Bullet Whisperer

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Reply #155 on: July 16, 2014, 10:37:49 pm
VERY impressive. Beautiful job. Was wondering it looks like the stand it's on has no ramp. Do you just pick it off when done.  ERC
Hmm ... yes ... that 'stand' is a new workbench specifically built quite recently by Ian for frame work. The frame was worked on ... then the bottom end and gearbox were put in to aid in the fabrication of an extra rear mounting point, which bolts to the back of the gearbox. The head and barrel are 'empty' of a piston at present - soon to be rectified - the front forks and swingarm have been added - and - before anyone realised it, a racing motorcycle is almost fully grown on the bench !!
 Team handed, we will lift it down before the wheels go on, but usually, bikes are built up on a bike lift, with the centre of the frame loop, or base of the engine resting on this wooden box, which has seen many projects through to completion ...
 B.W.


Bullet Whisperer

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Reply #156 on: July 18, 2014, 09:27:06 am
Here's what I will be putting into the race engine today ...


ace.cafe

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Reply #157 on: July 18, 2014, 01:02:14 pm
Beautiful!
Glad to see the coatings on it too.

Anticipation is intense!
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High On Octane

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Reply #158 on: July 18, 2014, 01:11:26 pm
Nice!  I think that is the most massive piston crown I have ever seen in ANY bike motor.  :)
2001 Harley Davidson Road King


Bullet Whisperer

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Reply #159 on: July 22, 2014, 08:35:13 am
More progress, although we probably won't be racing this machine this weekend, unless anything short of a miracle happens [I was waylaid by a Suzuki DR 350 needing its' front forks rebuilt for a couple of days. The forks did not come apart as they are supposed to and took AGES  ::) ]
 Anyway, I am now in the middle of setting the squish and bumping clearances between the head and the piston, before moving on to see what happens between the valves and piston when I know the required length of the pushrods and tailor them to suit and install them.
 I know I have to make a little more clearance between the sides of the combustion chamber and sides of the piston crown - I need to grab about 0.5 mm on either side adjacent to the exhaust valve area to achieve perfection. This engine could have been hastily assembled to top anything it has achieved previously, in order to have it racing this weekend, but that just wouldn't be good enough - there is so much more potential here, with the job done properly  ;)


ace.cafe

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Reply #160 on: July 22, 2014, 07:04:27 pm
Looking nice!
How thick is that lead solder wire?

BTW, once you find the right length for the push rods, it might not be a bad idea to have a set of 3/8" chrome moly steel ones with ~.100" wall thickness standing by, just in case.
There is a hell of a lot of spring pressure in there, multiplied x 1.45 at the pushrod side by the ratio. That will fold most pushrods in short order. I know you have unique pushrod design, and I'm not discounting that, but I do have concerns about it with such high forces involved. A spare pair of one-piece chrome moly won't hurt to have on hand, IMO.

I also recommend some molybdenum disulfide break-in lube be put on all the valve train contact surfaces, to reduce friction and wear.
And I recommend that the cam spindle fit into the timing cover be nice and tight. All this force will be acting directly on the cam spindles, and if they can wiggle around, they will. And that might cause them to fret/work loose on the end that is pressed into the engine case. Well supported spindles on both ends will help longevity.

I am SOOOO dying to witness the running of this thing!
I feel like a nervous relative when a baby is being born!
 8)
« Last Edit: July 22, 2014, 07:21:48 pm by ace.cafe »
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Bullet Whisperer

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Reply #161 on: July 22, 2014, 07:45:02 pm
Hi Ace,
 The solder is 1.5mm thick and after some doctoring, I now have a very good piston to combustion chamber side and squish clearance.
 The inlet valve to piston clearance is a little closer than I was expecting, but not dangerous by my reckoning. There is plenty of room between the exhaust valve and the piston crown when they reach their closest proximities.
 The engine top end is now assembled 'for keeps', and the C.R. is 14.25:1, according to my calculations, with 39cc of oil going into the combustion chamber at TDC and the permissible +0.060" overbore giving us an actual 517cc swept volume.
 I take on board your comments about the pushrods and even though everything is just about ready to go, the rockers will be coming out again, for shimming the end float. We also have to come up with some rocker cover studs to clear the rocker bodies, so I can get at the pushrods to measure them.
 The cam spindles are the Redditch non adjustable type and a good fit in the timing cover.
 Rest assured, everything will be well lubed, checked and monitored when start up time arrives !
 We had a good day with it today and it is back on the ground with the wheels on, here are the pictures:
 B.W.


ace.cafe

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Reply #162 on: July 22, 2014, 08:39:26 pm
My calculator says this:

Camshaft, Rod Length, and Altitude Correction to Compression

Your engine summary is as follows: Bore 3.367 inches, stroke 3.54 inches, rod c-c length 6.875 inches, with a static compression ratio of 14.25 :1. Your camshaft specifications call for an inlet valve closing of 75 degrees ABDC @ .050"(1.25mm) lift point.

Your chamber volume is 38.98 cc's. With this camshaft your dynamic, or effective stroke is 2.44 inches. Your dynamic compression ratio is 10.13 :1 corrected for cam timing, altitude, and rod length. Your dynamic cranking pressure, corrected for cam timing, rod length and sea level altitude is 215.17 PSI.



Pictures are looking awesome!

EDIT:
Looks like the intake valve is pretty close at TDC. There is a lot of piston dwell after TDC, and the valve will still be opening rapidly. Did you check it for clearance at 5-25 degrees ATDC?
About 1.5mm clearance is good, and it can go a little closer in a pinch. I woudn't go any closer than 1mm clearance.
And you can take into account that there will be at least .25mm-.3mm lash clearance added in when it's hot. Your closest proximity of piston to valve will be when it is cold.

I realize that you know this stuff, but I'm just nervously double checking everything!
 :)
« Last Edit: July 22, 2014, 09:00:34 pm by ace.cafe »
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Bullet Whisperer

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Reply #163 on: July 22, 2014, 11:14:53 pm
Hi Ace,
 The space between the inlet valve and piston crown was a little tight, as per the picture, the minimum clearance was 0.8mm, with no free play in the pushrod. However, I decided I would add an extra base gasket of 0.25mm, to give things a bit more room. Other options are running a slight valve clearance and / or retarding the inlet timing by a small amount. We also need to shim the long spark plug on the original plug side by a small amount, as the gap on this was closed right down as the piston was taken over TDC.
 The compression makes it feel like there is a brick in there when turning the engine via a spanner on the rotor nut ! [no such resistance with the plugs out, though]  ;)
 B.W.


ace.cafe

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Reply #164 on: July 23, 2014, 01:57:44 am
Hi Ace,
 The space between the inlet valve and piston crown was a little tight, as per the picture, the minimum clearance was 0.8mm, with no free play in the pushrod. However, I decided I would add an extra base gasket of 0.25mm, to give things a bit more room. Other options are running a slight valve clearance and / or retarding the inlet timing by a small amount. We also need to shim the long spark plug on the original plug side by a small amount, as the gap on this was closed right down as the piston was taken over TDC.
 The compression makes it feel like there is a brick in there when turning the engine via a spanner on the rotor nut ! [no such resistance with the plugs out, though]  ;)
 B.W.
Regarding the options, the standard practice when changing rocker ratio is to add .001" of cold lash for every tenth of rocker ratio that we add.
So, in your case of increasing the std 1:1 ratio to 1.45:1 ratio, should add at least .004"-.005" cold lash clearance at the valve when cold. This keeps the cam's lash ramp in proper relationship, so that the valve is not opening on the lash ramp.
Check this valve lash clearance at the valve, with an automotive style feeler gauge between the lash cap and the rocker roller wheel. Just like you do with a car that has solid tappets.
With .005" cold lash clearance, plus the .012" lash clearance that the typical Bullet grows to when hot, would give a working valve lash clearance of .017". That's nearly  a half millimeter when hot.
That is not an excessive lash distance for very high performance valve trains, and some automotive racing valve trains use as much as .028" lash on big lifting valve trains in racing. So, please don't be tempted to use the regular zero lash when cold type of valve lash setting with this new rocker package. We really will need to have this added lash for proper working with the cam.

So, for checking purposes, you could set a .015" cold lash, and then run your TDC check for valve clearance, and this will reflect very closely to what the actual clearance will be when the engine is hot with correct lash(being .002" on the conservative side). Then you can set the lash back to .004"-.005" at the valve for regular running.
« Last Edit: July 23, 2014, 02:13:52 am by ace.cafe »
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