Author Topic: Ace assisting Bullet Whisperer racing effort  (Read 124621 times)

0 Members and 2 Guests are viewing this topic.

High On Octane

  • Grand Gearhead
  • *****
  • Posts: 6,075
  • Karma: 0
Reply #420 on: October 05, 2015, 01:25:36 pm
That's great BW!  Impressive finish for how many bugs you guys had to sort out.  Great work!
2001 Harley Davidson Road King


ace.cafe

  • Grand Gearhead
  • *****
  • Posts: 14,457
  • Karma: 1
  • World leaders in performance/racing Bullets
Reply #421 on: October 05, 2015, 03:27:02 pm
That means they finished with points totals ahead of ALL the Norton Manx racers for the season, and only the two fastest G50 based bikes (Seeley?) scored higher!

I would say that's doing very well, especially for a Bullet!
Home of the Fireball 535 !


pknopp

  • Bulleteer
  • ***
  • Posts: 199
  • Karma: 0
Reply #422 on: October 06, 2015, 01:54:52 am
 I've been following on Facebook and I enjoy the posts and video's.
2000 Dlx


ace.cafe

  • Grand Gearhead
  • *****
  • Posts: 14,457
  • Karma: 1
  • World leaders in performance/racing Bullets
Home of the Fireball 535 !


Chuck D

  • Grand Gearhead
  • *****
  • Posts: 1,378
  • Karma: 0
Reply #424 on: October 06, 2015, 04:38:36 pm
HOT DAMN!
That's what a real bike sounds like! 8)
Ace "Fireball"#10 (Beefy the Bullet to her friends.)
 "Featherbed" frame by Rofomoto.

2017 Triumph T120


malky

  • Grand Gearhead
  • *****
  • Posts: 2,758
  • Karma: 0
  • Team Rough Inferior.
Reply #425 on: October 16, 2015, 01:53:45 pm
I have loved reading this thread, because it just goes to show what development and enthusiasm can achieve. I have always thought the Bullet is one of the most underrated bikes of all time. I wonder what could have been if Bill Lomas had stayed with Enfield and the company had the foresight to fully develop the d.o.h.c. engine. Looking at the race results, what ever happened to that fast B33 B.S.A. made ?. I think it was called a gold something or other. (Tongue firmly in cheek).
I was Molly Sugdens bridesmaid.

Spontaneity is the cure for best laid plans.
‘S Rioghal Mo Dhream


ace.cafe

  • Grand Gearhead
  • *****
  • Posts: 14,457
  • Karma: 1
  • World leaders in performance/racing Bullets
Reply #426 on: October 16, 2015, 02:17:39 pm
I have loved reading this thread, because it just goes to show what development and enthusiasm can achieve. I have always thought the Bullet is one of the most underrated bikes of all time. I wonder what could have been if Bill Lomas had stayed with Enfield and the company had the foresight to fully develop the d.o.h.c. engine. Looking at the race results, what ever happened to that fast B33 B.S.A. made ?. I think it was called a gold something or other. (Tongue firmly in cheek).

I personally believe that the pushrod valve gear can be(and has) improved to the point that it can do as well as OHC up to the rpms that these relatively long stroke engines can operate up to. There are pushrod drag racers and NASCAR racers which push 12000 rpm on pushrods with extremely high spring loads. I will grant that this places a lot of stress on that kind of valve train, and it might have short life, but it can do it in a racing application and be successful.

I consider the DOHC format more necessary for engines that rev higher than that. In our case, the valve gear is not the limiting factor. The limiting factor is clearly that we are running a longer stroke length than anybody else on the track, and that is highly stressful to the crank, including some breakages. The valve gear is handling the application, so far.

Now, with the pushrod vs DOHC situation, there are some advantages to the pushrod over the DOHC, particularly in vintage engines where the cams are physically located at one point above the valve buckets and cannot be moved. The cam buckets have a certain diameter, and the cams sit a certain distance above the buckets. This limits valve lift, and also some other things regarding valve motion. There is no form of "ratio multiplier" that typically is employed on these DOHC engines with the cams over the buckets. And even in some SOHC situations, the ratio is fixed by the dimensional layout of the parts.

In our Bullet with the pushrods, we were able to add a significant amount of rocker ratio with our package, and increase valve lift to over .600" , which AFAIK is higher lift than any of the competing engines with OHC can manage. So, in our case this pushrod package actually gives us an advantage over the OHC engines because we can lift higher, and the valve train can withstand the application of just as much revs as the others. With a shorter stroke length similar to theirs, we could reduce the crank stress and raise the rpm range to equivalent to theirs, and quite possibly then have the power advantage. Racing is all about pushing limits till things break, and then finding ways to push them further.

« Last Edit: October 16, 2015, 02:23:00 pm by ace.cafe »
Home of the Fireball 535 !


malky

  • Grand Gearhead
  • *****
  • Posts: 2,758
  • Karma: 0
  • Team Rough Inferior.
Reply #427 on: October 16, 2015, 03:38:09 pm
Reply much appreciated, and understood. Up here in wild and wooly Highland Scotland good engineering shops are few and ever decreasing. So we sometimes have to employ a bit of lateral thinking to get round"problems" .
I was Molly Sugdens bridesmaid.

Spontaneity is the cure for best laid plans.
‘S Rioghal Mo Dhream


Bullet Whisperer

  • Grand Gearhead
  • *****
  • Posts: 1,133
  • Karma: 1
Reply #428 on: May 17, 2016, 10:46:09 am
After missing the first round at Mallory Park, the 500 could be ready for the second round of this year's racing ...
 The 500 RE racer's engine is going back together and hopefully, this machine will be joining the rest of the bikes at Darley Moor for racing. The 3 piece crank has been specially made by Alpha Bearings, to, jointly mine and Alpha's specifications, to give an immensely strong component and much stronger than the standard setup on the timing side. There are two timing side roller bearings and the inboard one is huge, compared to the standard ones. The small, outboard bearing is just there to give a little extra support - every little helps, as they say! I made sure this crank design could fit into unmodified Redditch crankcases, so other Redditch engines of both 350cc and 500cc could benefit from a crank like this, without any modification work required in order to fit one.
 B.W.


Bullet Whisperer

  • Grand Gearhead
  • *****
  • Posts: 1,133
  • Karma: 1
Reply #429 on: May 17, 2016, 10:47:28 am
More pictures ...


ace.cafe

  • Grand Gearhead
  • *****
  • Posts: 14,457
  • Karma: 1
  • World leaders in performance/racing Bullets
Reply #430 on: May 17, 2016, 12:11:09 pm
Looks very robust!

Are there any oil drip feed drillings in the case above the bearing like the India Bullets have?
We extend them behind the outer race when we install the 2205 bearing on the timing side. I think it helps.
 :)
« Last Edit: May 17, 2016, 12:27:41 pm by ace.cafe »
Home of the Fireball 535 !


mevocgt

  • Grand Gearhead
  • *****
  • Posts: 1,020
  • Karma: 0
Reply #431 on: May 17, 2016, 09:09:34 pm
Woohoo! Gentalmen start your engines! ;D


Otto_Ing

  • Guest
Reply #432 on: May 17, 2016, 09:40:56 pm
More pictures ...

That is a serious bearing in there. The case looks as if it could be modified to take even a bigger one?


Bullet Whisperer

  • Grand Gearhead
  • *****
  • Posts: 1,133
  • Karma: 1
Reply #433 on: May 17, 2016, 09:46:28 pm
Are there any oil drip feed drillings in the case above the bearing like the India Bullets have?
Only on the drive side. The Redditch Bullets had a close fitting crankcase mainshaft boss, or sometimes a bronze bush on the timing side and these were scrolled to allow some oil from the timing chest to get to the bearing. I replaced the bronze bush in ours with a small needle race, so plenty of oil can get into both timing side mains with ease and give a bit of extra splash lubrication to the piston and barrel. The 500 and 350 have both used this design of mine for a few years, but this is the largest main bearing I have used to date  ;)
 B.W.


Bullet Whisperer

  • Grand Gearhead
  • *****
  • Posts: 1,133
  • Karma: 1
Reply #434 on: May 17, 2016, 09:50:12 pm
That is a serious bearing in there. The case looks as if it could be modified to take even a bigger one?
That might be possible, but the bearing I have chosen is huge and should be up to the job. It is also over 30% wider than any others usually found in there and no crankcase modification was required to fit it  8)
 B.W.