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  • Members: 605
  • Category: Motorcycles
  • Founded: Feb 24, 2001
  • Language: English
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#16895 From: "Carsten S." <charly@...>
Date: Sat Dec 12, 2009 10:59 am
Subject: 2012 MGP back to 1000cc, hence ...
rg500info
Send Email Send Email
 
2009 will be remembered as the turning point.
http://www.motogp.com/de/news/2009/FIM+announcement+for+2012+MotoGP

Further calculations allow to say, 2017 the 500cc 2-strokers will be on
the grid again!
Finally! ;-)

Cheers
Carsten (Aachen-Germany)

#16896 From: "Carsten S." <charly@...>
Date: Sat Dec 12, 2009 11:05 am
Subject: 1098R Super Build
rg500info
Send Email Send Email
 
#16897 From: "Carsten S." <charly@...>
Date: Sat Dec 12, 2009 11:19 am
Subject: Moped Archiv
rg500info
Send Email Send Email
 
http://www.users.globalnet.co.uk/~pattle/nacc/arcindex.htm
Awesome, isn't it?

Cheers
Carsten (Aachen-Germany)

#16898 From: Ian <iwd@...>
Date: Sun Dec 13, 2009 3:28 am
Subject: Re: Moto1
iwd@...
Send Email Send Email
 
>So here's the thing. Can anyone guess at a likely rev limit for a state
>of the art, racing 1000-4 with an 81mm bore?


I make that a minimum of 48.5mm stroke.   This gives a B/S ratio
of 1.67, which is not radical by any means.

At a relatively safe race MPS of 25.0 m/s, that comes to 15,465 rpm.

Pushing the friendship at MPS of 29.0 m/s comes to 17,940 rpm.



Cheers           IAN


See www.drysdalev8.com for :
- Drysdale 750-V8 Sports & 1000-V8 Cruiser
- DRYVTECH 2x2x2 Experimental
- Carberry Enfield 1000cc V-Twin
- Drysdale Hillclimb Open Wheeler

#16899 From: "Rick Denoon" <rdenoon@...>
Date: Sun Dec 13, 2009 4:49 pm
Subject: Throttle body chokes
rickd4004
Send Email Send Email
 
I've been working on adapting a set of CBR600RR EFI bodies onto my old CB400F project bike. I was originally going to sleeve down the entire body by inserting a machined aluminum sleeve to reduce the body diameter from 38mm down to 30mm, and use butterflies from an old set of CBR600F1 carbs.
 
My first 2 attempts have not been entirely successful in trying to get a perfect seal around the butterflies. (who could guess that my $2000 Chinese lathe/mill is not as accurate as Honda's production machinery?).
 
I started thinking about Weber carbs with their optional choke sizes, and from what I can see from some online manuals, the chokes seem to be placed upstream of the butterflies.
 
I started thinking that the easy solution would be to leave the 38mm butterfly portion of the throttle body intact, guaranteeing a good seal, and adding a choke upstream at the opening of the throttle body. I still need to choke down to about 26mm diameter at the intake port, so I would in effect have an intake system that probably started at about 34mm, necked down to 30mm, opened up to 38mm at the butterflies, and then necked back down to 26mm at the intake port.
 
 
Would this really be any better (or perhaps worst) than simply leaving the throttle body as is upstream of the butterflies and then just necking down to the 26mm intake port with a downstream insert?
 
Any thoughts would be appreciated,
 
Rick Denoon
 

#16900 From: Danny Whitfield <eco.usa@...>
Date: Mon Dec 14, 2009 12:36 am
Subject: Re: Throttle body chokes
danny_whitfield
Send Email Send Email
 


On Sun, Dec 13, 2009 at 11:49 AM, Rick Denoon <rdenoon@...> wrote:
 

I've been working on adapting a set of CBR600RR EFI bodies onto my old CB400F project bike. I was originally going to sleeve down the entire body by inserting a machined aluminum sleeve to reduce the body diameter from 38mm down to 30mm, and use butterflies from an old set of CBR600F1 carbs.
 
My first 2 attempts have not been entirely successful in trying to get a perfect seal around the butterflies. (who could guess that my $2000 Chinese lathe/mill is not as accurate as Honda's production machinery?).
 
I started thinking about Weber carbs with their optional choke sizes, and from what I can see from some online manuals, the chokes seem to be placed upstream of the butterflies.
 
I started thinking that the easy solution would be to leave the 38mm butterfly portion of the throttle body intact, guaranteeing a good seal, and adding a choke upstream at the opening of the throttle body. I still need to choke down to about 26mm diameter at the intake port, so I would in effect have an intake system that probably started at about 34mm, necked down to 30mm, opened up to 38mm at the butterflies, and then necked back down to 26mm at the intake port.
 
 
Would this really be any better (or perhaps worst) than simply leaving the throttle body as is upstream of the butterflies and then just necking down to the 26mm intake port with a downstream insert?
 
Any thoughts would be appreciated,
 
Rick Denoon

My thought is that you could do better with an induction system that is sized closer to your 26mm intake port.

Dan Whitfield


 


#16901 From: Geo <caparo.g@...>
Date: Mon Dec 14, 2009 12:21 pm
Subject: Re: Throttle body chokes
yamaha_george
Send Email Send Email
 
On Monday 14 December 2009 00:36:16 Danny Whitfield wrote:
> On Sun, Dec 13, 2009 at 11:49 AM, Rick Denoon <rdenoon@...> wrote:
> > I've been working on adapting a set of CBR600RR EFI bodies onto my old
> > CB400F project bike. I was originally going to sleeve down the entire
> > body by inserting a machined aluminum sleeve to reduce the body diameter
> > from 38mm down to 30mm, and use butterflies from an old set of CBR600F1
> > carbs.
> >
> > My first 2 attempts have not been entirely successful in trying to get a
> > perfect seal around the butterflies. (who could guess that my $2000
> > Chinese lathe/mill is not as accurate as Honda's production machinery?).
> >
> > I started thinking about Weber carbs with their optional choke sizes, and
> > from what I can see from some online manuals, the chokes seem to be
> > placed upstream of the butterflies.
> >
> > I started thinking that the easy solution would be to leave the 38mm
> > butterfly portion of the throttle body intact, guaranteeing a good seal,
> > and adding a choke upstream at the opening of the throttle body. I still
> > need to choke down to about 26mm diameter at the intake port, so I would
> > in effect have an intake system that probably started at about 34mm,
> > necked down to 30mm, opened up to 38mm at the butterflies, and then
> > necked back down to 26mm at the intake port.
> >
> > See http://www.denoonsp.com/miscellaneous-photos-ii.htm
> >
> > Would this really be any better (or perhaps worst) than simply leaving
> > the throttle body as is upstream of the butterflies and then just necking
> > down to the 26mm intake port with a downstream insert?
> >
> > Any thoughts would be appreciated,
> >
> > Rick Denoon
>
> My thought is that you could do better with an induction system that is
> sized closer to your 26mm intake port.
>
> Dan Whitfield

Hi,
  it has always been my impression that air velocity was not critical on efi
systems as it could be compensated for by the electronics controlling the
fuel.
         I can understand that you do not want a "ledge" between body & intake
port but rather a slope from the rear side of the butterfly down to inlet
size & leave the rest of the body untouched

--
TTFN
    Caparo

#16902 From: Ian <iwd@...>
Date: Mon Dec 14, 2009 12:48 pm
Subject: Re: Throttle body chokes
iwd@...
Send Email Send Email
 
>it has always been my impression that air velocity was not critical on efi
>systems



Not as critical but you still want it within a reasonable range of the
original carb but it depends on where the injector itself is sited too.



Cheers          IAN


See www.drysdalev8.com for :
- Drysdale 750-V8 Sports & 1000-V8 Cruiser
- DRYVTECH 2x2x2 Experimental
- Carberry Enfield 1000cc V-Twin
- Drysdale Hillclimb Open Wheeler

#16903 From: "Glenn Thomson" <rdguy@...>
Date: Mon Dec 14, 2009 2:07 pm
Subject: Another homegrown V-twin
rd_glenn
Send Email Send Email
 
#16904 From: Ian <iwd@...>
Date: Mon Dec 14, 2009 10:28 pm
Subject: Re: Another homegrown V-twin
iwd@...
Send Email Send Email
 
>They're everywhere!
>
><http://movinmikes.com/HONDA_XR75_V-TWIN.php>http://movinmikes.com/HONDA_XR75_V\
-TWIN.php


That looks like a very nice job, the cylinders are offset, so he hasn't gone
for the one cam chain drive sprocket with super long camchain theory.

I love to see people wasting time on pointless projects, where would we be
without them !!



Cheers           IAN


See www.drysdalev8.com for :
- Drysdale 750-V8 Sports & 1000-V8 Cruiser
- DRYVTECH 2x2x2 Experimental
- Carberry Enfield 1000cc V-Twin
- Drysdale Hillclimb Open Wheeler

#16905 From: "gregsummerton" <gregss@...>
Date: Tue Dec 15, 2009 1:35 am
Subject: Re: Another homegrown V-twin
gregsummerton
Send Email Send Email
 
Ian,Glenn
I took a pic of a similar bike at Broadford (Australia) this last Easter.
I've placed it in the photo section of this list.
No idea who built it.

My thoughts were: "All that effort for what real purpose?"

Other than a 'because it was there to do' kind of thing
There is no real reason, but that is the attraction I guess. Amazing!

So the claim in that website that "you will not see another one in the world" is
not quite 100% accurate.

At least it proves that all the nutters aint just in one part of the world.
Greg


--- In mc-engine@yahoogroups.com, Ian <iwd@...> wrote:
>
>
> >They're everywhere!
> >
>
><http://movinmikes.com/HONDA_XR75_V-TWIN.php>http://movinmikes.com/HONDA_XR75_V\
-TWIN.php
>
>
> That looks like a very nice job, the cylinders are offset, so he hasn't gone
> for the one cam chain drive sprocket with super long camchain theory.
>
> I love to see people wasting time on pointless projects, where would we be
> without them !!
>
>
>
> Cheers           IAN
>

#16906 From: Ian <iwd@...>
Date: Tue Dec 15, 2009 2:16 am
Subject: Re: Another homegrown V-twin
iwd@...
Send Email Send Email
 
>There is no real reason, but that is the attraction I guess. Amazing!


Exactly, as I said, completely pointless projects such as this
should be encouraged.


>So the claim in that website that "you will not see another one in
>the world" is not quite 100% accurate.


Some guy in England did some very nasty Honda 90 twins - Millyard maybe ?



Cheers                  IAN


See www.drysdalev8.com for :
- Drysdale 750-V8 Sports & 1000-V8 Cruiser
- DRYVTECH 2x2x2 Experimental
- Carberry Enfield 1000cc V-Twin
- Drysdale Hillclimb Open Wheeler

#16907 From: Geo <caparo.g@...>
Date: Tue Dec 15, 2009 9:41 am
Subject: Re: Another homegrown V-twin
yamaha_george
Send Email Send Email
 
On Tuesday 15 December 2009 02:16:11 Ian wrote:
> >There is no real reason, but that is the attraction I guess. Amazing!
>
> Exactly, as I said, completely pointless projects such as this
> should be encouraged.
>
> >So the claim in that website that "you will not see another one in
> >the world" is not quite 100% accurate.
>
> Some guy in England did some very nasty Honda 90 twins - Millyard maybe ?
>
>
>
> Cheers                  IAN
>
>
> See www.drysdalev8.com for :
> - Drysdale 750-V8 Sports & 1000-V8 Cruiser
> - DRYVTECH 2x2x2 Experimental
> - Carberry Enfield 1000cc V-Twin
> - Drysdale Hillclimb Open Wheeler
Ian,
  I have never seen Millyards Honda's but I watched him make his quinline (5
cylinder ) Kawasaki's with just hand tools,  some nifty jigs & a welding set.
  A thing to behold for sure and all with a show crowd pestering him, none of
this here is one I made earlier nonsense..
You can see snap shots of the build at:-

           http://www.saltmine.org.uk/kgb/mechshow.html






--
TTFN
    Caparo

#16908 From: "jimh18t" <jimandcat@...>
Date: Wed Dec 16, 2009 12:02 pm
Subject: Honda Blackbird engine CAD model / drawing
jimh18t
Send Email Send Email
 
Hi Folks,
Would any of you guys know where I can get a CAD model of a Honda Blackbird
engine from?

regards
Jim, Lincoln, UK

#16909 From: "Michael Moore" <mmoore@...>
Date: Mon Dec 21, 2009 4:53 pm
Subject: Cutaway ZX14 engine photos
mmooreeurosp...
Send Email Send Email
 
http://tinyurl.com/yenklu5

They are better than the typical postage-stamp sized ones.

cheers,
Michael

#16910 From: "Jim Schneider" <swissscf@...>
Date: Sat Dec 26, 2009 8:31 pm
Subject: gear dog support
swiss_88310
Send Email Send Email
 
Hey Guys,
 
My favorite vintage engine is the Honda XL350 from the mid-'70s.  One of the problems that they have is a weak 3rd gear in the tranny.  There have been a few fixes over the years including "New" gears made up by formerly Webster Gears, altered Primary gear ratio to reduce the torque input from the crank to the clutch/tranny, Cryo-treating (which Ken helped me with) and last but not least re-inforcement of the gear by welding a washer around the gear engagement dogs/ears.  I am cranking some real power into this engine and for various reasons I do not have the custom Webster gearset.  First reason is that I swapped in a TL-250 gearset which converted the engine to a Wide-Ratio set and the Webster does not match the different 3rd and 4th gear ratios.  So I am stuck trying to do everything that I can to help the stock TL gears live a long and full life and not break into several different pieces. 
You can see the mod that I am looking at on my Photobucket page at
 
This was an early fix for the gears and consisted of welding a supporting washer around the 3 gear tabs.  The welds are centered in the middle of the gear near the shaft and not at the tabs or the gear teeth.  Thing is that I am concerned with affecting the heat treat of the gear with this kind of welding.  I have looked at different solutions to do basically the same thing.  Two ideas that are being considered are Silver Soldering the washer or finding a suitable Epoxy formula to glue the washer to the gear.  Both of these have some advantages over the pictured Heli-arc welds because they could penetrate the surface directly between the washer and the gear surrounding the tabs and fully around the upper ring shown in the pictures.  I also noticed that if I reduced the center hole diameter of the washer (4130 plate) to the OD of the tranny shaft it would allow the epoxy or Silver Solder to bond to the sunken center area of the gear also, adding again to the overall strength of the set-up. 
 
The Silver Soldering although not as high a heat level as a Tig weld, would still need a LOT of heat throughout the entire gear in order to bring the temp up high enough to bond the Silver Solder.  
 
An Epoxy would keep any heat problems from affecting the gear heat treat, but most of the "Brand Name" epoxies that I have found are lower temp rated.  The Devcon product is only rated to a little over 100 degrees F.  Some of the off brands are saying 275-300 degrees but I don't know whether to trust their ratings or not?  Of course, has to be chemical/oil tolerant!
 
Suggestions or ideas?
 
Thanks,
Swiss 

#16911 From: "marshengnz" <helen.wallace@...>
Date: Sat Dec 26, 2009 9:49 pm
Subject: Re: gear dog support
marshengnz
Send Email Send Email
 
Hi Swiss

I wouldn't trust epoxy in this application.

I would speak to your local metal heat treatment company.

My suggestion would be

anneal the whole gear, Mig / Tig on the washer and then reharden or nitride it.

Cheers Wallace

#16912 From: "marshengnz" <helen.wallace@...>
Date: Sat Dec 26, 2009 9:49 pm
Subject: Starting rollers
marshengnz
Send Email Send Email
 
Hi Everyone.

Anyone get an MV Augsta for Christmas ?

I need to make some starting rollers. It is for a 500 single with 12:1
compression so it needs to be correct.

Anyone have suggestions on the following.

Roller surface speed and Roller material

Would rubber be better than steel for the roller. I was thinking of a boat
transom roller.

If the steel is knurled, I'd hate to cut a nice slot in my slick.

Cheers Wallace

#16913 From: "Jim Schneider" <swissscf@...>
Date: Sat Dec 26, 2009 9:55 pm
Subject: RE: gear dog support
swiss_88310
Send Email Send Email
 
Sorry, no local heat treating company!  My local machinist would heat it with a torch and then drop it in oil or stick it under a coffee can for slow cool depending on whether he was annealing or heat treating it.  Had him do a countershaft sprocket one time so that I could change the bolt holes.
 
Swiss
 
-----Original Message-----
From: mc-engine@yahoogroups.com [mailto:mc-engine@yahoogroups.com] On Behalf Of marshengnz
Sent: Saturday, December 26, 2009 2:49 PM
To: mc-engine@yahoogroups.com
Subject: Re: gear dog support

 

Hi Swiss

I wouldn't trust epoxy in this application.

I would speak to your local metal heat treatment company.

My suggestion would be

anneal the whole gear, Mig / Tig on the washer and then reharden or nitride it.

Cheers Wallace


#16914 From: Ken Canaga <kcanaga@...>
Date: Sun Dec 27, 2009 2:05 am
Subject: Re: Starting rollers
kcanaga
Send Email Send Email
 
I have a set of DocZ electric rollers, and they use glued on friction
material, the same sort you see on stairs for non-slip. They work well,
and definitely don't tear up the slicks. They do have to be replaced
occasionally. I think he sells some sort of knurled rollers now, but
mine is the older model. I've used it to start a variety of big singles,
from 500 cc to 700cc, with CR up to 12.5:1. Starting on the rollers does
take the right technique for big singles. It really helps to back the
bike up to compression, and then put it on the rollers with the clutch
in, spin the rollers up, and drop the clutch aggresively. Sometimes it
takes a little help from a friend pushing down on the rear of the bike.
I've seen a lot of home-brew rollers at the track that use knurled
rollers, and they don't seem to cause any wear problems with slicks. I
have seen tires get gooves from the rollers, but they were from the rear
wheel sliding over to the side and finding a nice sharp piece of metal
to rub against. If you make your own rollers, be sure to put some side
rollers on to limit sideways movement of the rear tire. One of the
slickest home-brew starters I recall used a large aluminum rear roller
with side flanges, so it looked like a large v-belt pulley. It was just
wide enough to hold the tire, and the v-shaped sides located it in the
center quite nicely. This particular system used a small Honda gas
engine, 4-6 hp or so, with a centrifugal clutch, to drive the rear
roller. The front roller was just a simple undriven cylinder on ball
bearings. There was a foot pedal throttle for it, so the rider could
fire up the engine, roll his bike back onto the rollers, step on the
foot throttle untill the centrifugal clutch engaged, drop the bike
clutch, and fire up. I think there was a way for him to turn the engine
off from the saddle, but I don't recall that part too well. The other
interesting feature of this starter was a folding aluminum sheet of two
or three sections, maybe a foot wide, that was connected to the starter
assembly. When unfolded, it extened in front of the starter far enough
for the bike front wheel to sit on it. With the front brake on, that
kept the bike from running off the starter. The whole system was very
lightweight, and I was quite impressed with it. Gil Vaillencourt had it
as part of his Works Performance vintage race team. He's probably still
using it.

I've always thought that it would be helpful to have a heavy flywheel
somewhere in the drive train for the rollers. You could spin it up to
speed before dropping the clutch, and it would help overcome the intial
compression stroke resistance. Unfortunately, that would make an already
heavy piece of pit equipment even heavier to lug around.

All the rollers I've seen in use at the track use either aluminum or
steel rollers. If you don't need to be able to start the bike alone,
there's always the start cart with a gas engine with a small tire driven
directly off the crank, like the Motogp teams use. That's a really
simple system, but it does require two people, and a suitable rear wheel
stand for the bike.

We used to use rollers driven by a car rear wheel at the track. Simple,
easy, fairly light wheight, and cheap, and you could really spin them up
if needed. Basic steel rollers with no knurling, grooving, etc. Seemed
to have more than enough friction with the tire. I bought the electric
rollers more to have an easy way to start the bike at my shop, and then
discovered that they were really convenient at the track. We set them up
right in front of our canopy, and if the rider was in a hurry, he could
just roll up on them, step on the foot control, fire up, and ride away.
No need to find someone to jump in the truck and fire it up for the rollers.

Ken C.

marshengnz wrote:
>
> Hi Everyone.
>
> Anyone get an MV Augsta for Christmas ?
>
> I need to make some starting rollers. It is for a 500 single with 12:1
> compression so it needs to be correct.
>
> Anyone have suggestions on the following.
>
> Roller surface speed and Roller material
>
> Would rubber be better than steel for the roller. I was thinking of a
> boat transom roller.
>
> If the steel is knurled, I'd hate to cut a nice slot in my slick.
>
> Cheers Wallace
>
>

#16915 From: "David Kath" <bsa_gs@...>
Date: Sun Dec 27, 2009 2:29 am
Subject: Re: Starting rollers
bsa_gs@...
Send Email Send Email
 
Geez ... just build/buy a starter that plugs on to the crank as hundreds of
dirt track racers have done for many years. No need to revent the wheel.
BTW,  rollers suck.
dave - NV

#16916 From: "kcanaga" <kcanaga@...>
Date: Sun Dec 27, 2009 2:45 am
Subject: Re: Starting rollers
kcanaga
Send Email Send Email
 
Yeah, I like them too.  I use one for the Norton and Rotax engined bikes, and
would probably convert the others if I was still seriously racing.  The only
problem with them is that they generally require two people to start the bike,
the rider with a hand on the throttle, and a helper with two hands for the
starter.  I can sometimes start the bikes with no hand on the throttle, but not
always.  Not much of a problem unless you like to do things without having to
rely on a helper.

Ken

--- In mc-engine@yahoogroups.com, "David Kath" <bsa_gs@...> wrote:
>
> Geez ... just build/buy a starter that plugs on to the crank as hundreds of
> dirt track racers have done for many years. No need to revent the wheel.
> BTW,  rollers suck.
> dave - NV
>

#16917 From: GStarRon@...
Date: Sat Dec 26, 2009 10:08 pm
Subject: Re: Starting rollers
gsr6042000
Send Email Send Email
 
Very few think I am sane... but I love having a compression release... sure makes starting easy, even at 13:1 C/R... no rollers needed...
 
Cheers..!
 
Ron
 
 
In a message dated 12/26/2009 1:49:56 P.M. Pacific Standard Time, helen.wallace@... writes:
I need to make some starting rollers. It is for a 500 single with 12:1 compression so it needs to be correct.

Anyone have suggestions on the following.

Roller surface speed and Roller material

Would rubber be better than steel for the roller. I was thinking of a boat transom roller.

If the steel is knurled, I'd hate to cut a nice slot in my slick.

Cheers Wallace




#16918 From: John Fisher <john@...>
Date: Sun Dec 27, 2009 5:57 pm
Subject: Re: Starting rollers
byrd_fishers
Send Email Send Email
 
If I read Alan's reply correctly, he was describing something the Buell
guys used to use. It had a wheelbarrow wheel or similar attached to a
lawnmower engine on a two-wheeled frame a bit like the stand for a mig
welder. You just backed up the rack to the bike, and I am pretty sure
spun up the wheel and then touched it to the bike rear. It may have used
the weight of the engine to press the wheel against the bike tire... an
electric version would be just as easy to make.

It seemed easier to use in the pits than powered starting rollers, but YMMV.

JF

#16919 From: "ausrobg" <ausrobg@...>
Date: Sun Dec 27, 2009 11:02 pm
Subject: Re: Starting rollers
ausrobg
Send Email Send Email
 
I know a guy that kickstarts his 14:1 Jawa grasstrack bike without compression
release or any ignition retard (methanol).

He says you have to be a bit "brutal" with your kick !!!

Cheers,

Rob

--- In mc-engine@yahoogroups.com, GStarRon@... wrote:
>
> Very few think I am sane... but I love having a compression  release...
> sure makes starting easy, even at 13:1 C/R... no rollers  needed...
>
> Cheers..!
>
> Ron
>
>
>

#16920 From: "RohanB" <newboltz333@...>
Date: Sun Dec 27, 2009 11:28 pm
Subject: Re: Starting rollers
newboltz333@...
Send Email Send Email
 
In this neck of the woods, a lot of race folks use a pair of longer rollers
that slip under the back wheel of a car. Start car, put in gear, back wheel
spins rollers.  Rollers extend out far enough to roll bike back onto
rollers and start it. Need the missus or a helper to do the car stuff,
obviously.

P.S. Make sure car doesn't have a slippery diff (LSD).

Opethiselps.

#16921 From: Ian <iwd@...>
Date: Mon Dec 28, 2009 6:16 am
Subject: Re: gear dog support
iwd@...
Send Email Send Email
 
>My favorite vintage engine is the Honda XL350 from the mid-'70s.


Mine too - I had a very hot ( later ) centre port engine in a Bultaco frame
and the thing was a weapon on flat track circuits.  I raced it in the desert
and MX too.


>Thing is that I am concerned with affecting the heat treat of the
>gear with this kind of welding.


As shown in the photos, I wouldn't worry about any adverse affect on
the heat treatment.  The welds are far enough away from the teeth as
to have no affect, and the splines have so much contact area that it
won't worry them if they are a little softer up one end.

New gears ( with meatier dogs ) are the obvious answer.


Cheers             IAN


See www.drysdalev8.com for :
- Drysdale 750-V8 Sports & 1000-V8 Cruiser
- DRYVTECH 2x2x2 Experimental
- Carberry Enfield 1000cc V-Twin
- Drysdale Hillclimb Open Wheeler

#16922 From: "marshengnz" <helen.wallace@...>
Date: Mon Dec 28, 2009 9:13 pm
Subject: Re: Starting rollers
marshengnz
Send Email Send Email
 
-- In mc-engine@yahoogroups.com, "ausrobg" <ausrobg@...> wrote:
>
> I know a guy that kickstarts his 14:1 Jawa grasstrack bike without compression
release or any ignition retard (methanol).
>


I have two problems,

I have the EI carb on the SR500 and it does not have idle circuits so it is not
that easy to start.

I'm racing both F4 (buckets) and pre82 and pre82 it is straight after  buckets.
I do not have any time to mess around between races. I normally have to park the
pre82 on the dummy grid to be ready in time. I have already have missed a race
or two being too slow.

#16923 From: "Jim Schneider" <swissscf@...>
Date: Tue Dec 29, 2009 2:06 am
Subject: RE: Starting rollers
swiss_88310
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Best that I have seen this done is to have a family member or friend hold the running bike waiting for you to finish the first race and start the second.  That way the second engine isn't cold when you hit the start line and is ready to race.  Of course with no idle circuit in the carbs your "assistant" would need to keep it running just above idle in order to keep it from dying and spoiling the whole plan.  Noticed that on the new MX250cc Honda 4-stroke they specify an idle rpm of 2k rpm or more!  Hate to have it die due to a low rpm bog!!!
 
Swiss
 
-----Original Message-----
From: mc-engine@yahoogroups.com [mailto:mc-engine@yahoogroups.com] On Behalf Of marshengnz
Sent: Monday, December 28, 2009 2:13 PM
To: mc-engine@yahoogroups.com
Subject: Re: Starting rollers

 

-- In mc-engine@yahoogroups.com, "ausrobg" <ausrobg@...> wrote:
>
> I know a guy that kickstarts his 14:1 Jawa grasstrack bike without compression release or any ignition retard (methanol).
>

I have two problems,

I have the EI carb on the SR500 and it does not have idle circuits so it is not that easy to start.

I'm racing both F4 (buckets) and pre82 and pre82 it is straight after buckets. I do not have any time to mess around between races. I normally have to park the pre82 on the dummy grid to be ready in time. I have already have missed a race or two being too slow.


#16924 From: Ian <iwd@...>
Date: Tue Dec 29, 2009 5:25 am
Subject: RE: Starting rollers
iwd@...
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>Noticed that on the new MX250cc Honda 4-stroke they specify an idle
>rpm of 2k rpm or more!



With a 50mm Throttle Body on a 250cc single, it would need 2krpm to
know that there is any air flow thru the TB !!



Cheers            IAN


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