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Wayne Baker
Level 1 Member
New South Wales
10 Posts |
 Posted - 13 Jun 2010 : 11:18:10 PM
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Thinking about putting this bike on the track
Where can I get expansion chamber design for this engine?
Would a chamber from an RD 250 do & where might I get one of those?
Can i run 17inch wheels with Bridgestone Battlaxe tyres?
What class would it be in?
Is this bike a "Bucket"?
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john feakes
Advanced Member
Victoria
791 Posts |
Posted - 14 Jun 2010 : 10:13:31 AM
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Wayne, this bike would be a P5 125.
Buckets are, as far as I know, currently limited to 111cc for 2 strokes.
18" wheels unless originally fitted with 17s.
PM sent.
Regards, John |
125 RIDERS' ALLIANCE
A wise person simplifies the complicated, a fool complicates the simple. |
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Alan Cotterell
In a time out state
Victoria
421 Posts |
Posted - 14 Jun 2010 : 10:18:26 AM
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| One less bike for the bucket grid? |
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john feakes
Advanced Member
Victoria
791 Posts |
Posted - 14 Jun 2010 : 10:24:28 AM
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| Perhaps one more for the 125 grid. |
125 RIDERS' ALLIANCE
A wise person simplifies the complicated, a fool complicates the simple. |
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Wayne Baker
Level 1 Member
New South Wales
10 Posts |
Posted - 14 Jun 2010 : 12:52:16 PM
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| If then a P5 125 & not a bucket, do I have to stick with 18inch wheels or can I use 17inch? I ask because I have access to the newer smaller wheels rather than the VERY heavy stock steel wire spoke wheels. How about fairings & seat? I have access to my son,s spares bin - he races a Honda 125 GP bike & has a collection of "pre-loved" fibreglass bits - I will need to develop my FRP repair skils! |
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john feakes
Advanced Member
Victoria
791 Posts |
Posted - 14 Jun 2010 : 1:41:11 PM
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Wayne, the key to your wheels is what it was originally supplied with.
Get hold of your son's copy of the M.A. rule book and study chapter 16.
Machines are to be visually compatible with the period they represent so any parts need to be of period design.
MatchoMick does a great range of tanks, seats and fairings for historic bikes.
Check out Moto Tumbi.
It would be worth having a chat to M.A. before you build something that may not be eligible for a log book. Call Ross Martin at M.A.
Cheers, John |
125 RIDERS' ALLIANCE
A wise person simplifies the complicated, a fool complicates the simple. |
Edited by - john feakes on 14 Jun 2010 2:16:49 PM |
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Bummers
Level 3 Member
Queensland
244 Posts |
Posted - 14 Jun 2010 : 3:49:42 PM
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Wayne I think you are stuck with 18" wheels unless you can bore it out to over 500cc you are stuck with 18" wheels. The Battlax BT39s are good, available & much better priced than the Avons. Your best bet is to make up a set of decent lightweight wire wheels in the sizes to suit the tyres, probably 1.85 on the front & a 2.15 on the rear. Disc brakes both ends are allowed & the best shock(s)you can afford.
Racetech bits in the front forks work well & give you some adjustability.
If you want to farm out the engine work work I know a guy (in Brisbane) who could be interested in doing the porting & a pipe for it. PM me if interested & I'll suss it out. |
“Racing is life. Anything before or after is just waiting.” Steve McQueen |
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Alan Cotterell
In a time out state
Victoria
421 Posts |
Posted - 15 Jun 2010 : 06:32:35 AM
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| I wonder why P4 & P5 125s cannot run with 'buckets'? Perhaps our rules should have specific exclusions to keep out the models which would blitz everybody else? Seems ridiculous that a combined grid couldn't be used? |
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john feakes
Advanced Member
Victoria
791 Posts |
Posted - 15 Jun 2010 : 12:13:09 PM
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Al, P4 and P5 125 4 STROKES can run with buckets and generally do.
2 strokes can't because of the capacity limit imposed on buckets.
Buckets that are log booked can and do run in historic events.
In essence, some can, some can't.
Cheers, John |
125 RIDERS' ALLIANCE
A wise person simplifies the complicated, a fool complicates the simple. |
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Alan Cotterell
In a time out state
Victoria
421 Posts |
Posted - 16 Jun 2010 : 07:41:06 AM
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| That sounds sensible. Are bucket races always run at historic meetings, with historic 125cc fourstrokes involved. It would seem a sensible way to get a full grid of tiddlers? |
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john feakes
Advanced Member
Victoria
791 Posts |
Posted - 16 Jun 2010 : 09:41:17 AM
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Al, it is the other way round. Bucket races are not part of historic racing because buckets are not an historic class and most of them don't have and can't get log books, they are generally not old enough.
However some historic 4 stroke 125s do run in the bucket races.
Cheers, John |
125 RIDERS' ALLIANCE
A wise person simplifies the complicated, a fool complicates the simple. |
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Alan Cotterell
In a time out state
Victoria
421 Posts |
Posted - 19 Jun 2010 : 09:03:28 AM
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| Perhaps bucket races should be run regularly at historic meetings - no log books required? That way we might get new people into historics? |
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revhd
Level 2 Member
Victoria
108 Posts |
Posted - 19 Jun 2010 : 1:47:51 PM
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I suggested that a while back ,but from memory got a got a negative response from g.d.
I think it would work very well and as u say we would get some riders getting log books and switching over.
Certainly something worth looking at i think. |
125 alliance |
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john feakes
Advanced Member
Victoria
791 Posts |
Posted - 19 Jun 2010 : 3:15:06 PM
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I wonder what the political situation would be?
Technically it would mean running two races at the same time, one historic and one "modern".
I will study them thar rools to see what I can learn. |
125 RIDERS' ALLIANCE
A wise person simplifies the complicated, a fool complicates the simple. |
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GD66
Senior Member
Western Australia
390 Posts |
Posted - 19 Jun 2010 : 4:13:42 PM
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quote:
Originally posted by revhd
I suggested that a while back ,but from memory got a got a negative response from g.d.
Certainly wouldn't be from me, Peter. I'm all for whatever it takes to get new gallopers out onto the track. Our club has just auctioned two buckets to new members and we'll be doing what we can to get them out there racing on the cheap. |
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john feakes
Advanced Member
Victoria
791 Posts |
Posted - 19 Jun 2010 : 4:30:41 PM
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I think that was a typo and meant to be J.D.
I remember there being some idea that bucket racers argued too much and would be more bother than they were worth. |
125 RIDERS' ALLIANCE
A wise person simplifies the complicated, a fool complicates the simple. |
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Alan Cotterell
In a time out state
Victoria
421 Posts |
Posted - 19 Jun 2010 : 5:43:44 PM
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| Perhaps 'arguing too much' might really mean their arguments were sensible, persuasive, progressive, and not in keeping with our traditional negativity? I find it difficult to comprehend why we cannot have a FREE class for tiddlers, to bring new people into our sport. There are simply too many rules, and they're stuffing this class. |
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revhd
Level 2 Member
Victoria
108 Posts |
Posted - 19 Jun 2010 : 9:50:45 PM
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| yes sorry gd66 i did mean J.D.... i still think its a good idea |
125 alliance |
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john feakes
Advanced Member
Victoria
791 Posts |
Posted - 20 Jun 2010 : 10:02:14 AM
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So do I.
Anything that gets more bikes on the track will benefit everyone with the interests of the sport at heart.
The more bikes the less $$$$$$$ to participate. |
125 RIDERS' ALLIANCE
A wise person simplifies the complicated, a fool complicates the simple. |
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john feakes
Advanced Member
Victoria
791 Posts |
Posted - 20 Jun 2010 : 10:05:36 AM
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Now, what of Wayne and his proposed bike?
Any developments up there? |
125 RIDERS' ALLIANCE
A wise person simplifies the complicated, a fool complicates the simple. |
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Wayne Baker
Level 1 Member
New South Wales
10 Posts |
Posted - 23 Jun 2010 : 11:25:42 PM
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| Thanks John - any advice / hints that I can get, especially re carb, porting, ignition and mainly the exhaust. Anyone got experience with these little Yammy 2-strokes? It's only meant to e a bit of fun and not a money pit! |
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Alan Cotterell
In a time out state
Victoria
421 Posts |
Posted - 24 Jun 2010 : 08:17:59 AM
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| It's easy to get a two stroke going quick, but the wear rate becomes a problem. It all costs money. How many gears have you got - that's the starting point. Next is the ignition system. |
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Wayne Baker
Level 1 Member
New South Wales
10 Posts |
Posted - 26 Jun 2010 : 6:35:55 PM
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| Thanks again - it has the standard 5 sped box, actually standard everything! what can be done to the ignition? I am not a mechanic but can manage al fabrication whether in steel, plastic, fibreglass. Am I expecting too much of this little jigger? Is this a common bike to start with or am I better off with something else? It owes me nothing and I'm just after a bit of fun, not trying to win a world title! |
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Wayne Baker
Level 1 Member
New South Wales
10 Posts |
Posted - 26 Jun 2010 : 6:38:16 PM
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| Back again. Still wondering about the exhaust. Anyone got any suggestions? I've been looking at chamber design on the 'net & so far the maths is amazing! Anyone got a simpler approach? |
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Wayne Baker
Level 1 Member
New South Wales
10 Posts |
Posted - 26 Jun 2010 : 8:51:56 PM
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Back again, again:
2 more questions:
I see a bloke on this forum doing a CB125 Honda as a P4 bike - what's the difference between this & a "bucket"?
& back to my little Yammie - I will have al the lights, mudguards, seat , tank etc left over - anyone need all this stuff? |
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john feakes
Advanced Member
Victoria
791 Posts |
Posted - 27 Jun 2010 : 10:47:02 AM
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Wayne, a CB125 can run as a bucket as it is a 4 stroke and is well under the 4 stroke capacity limit. Buckets have smaller capacity limits imposed on 2 strokes in an attempt to level the playing field.
Check the Bucket Racing Association for detailed information.
Cheers, John |
125 RIDERS' ALLIANCE
A wise person simplifies the complicated, a fool complicates the simple. |
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Wayne Baker
Level 1 Member
New South Wales
10 Posts |
Posted - 27 Jun 2010 : 10:54:01 AM
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so then could the cb125 run as both a p4 & a bucket?
what's the difference between p4 & p5? |
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Bummers
Level 3 Member
Queensland
244 Posts |
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Wayne Baker
Level 1 Member
New South Wales
10 Posts |
Posted - 27 Jun 2010 : 7:41:15 PM
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Also I have had a look at the Bucket Website, which has this confusing information:
111cc for air-cooled 2-strokes,
but includes Yamaha rx125 frame & engine on the list of homologated equipment.
So is this engine not a full 125?
Wayne |
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Wayne Baker
Level 1 Member
New South Wales
10 Posts |
Posted - 27 Jun 2010 : 7:48:58 PM
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Back again:
the Bucket Website also includes Yamaha DT175 engines - how does that fit in with the 111cc limit? |
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Alan Cotterell
In a time out state
Victoria
421 Posts |
Posted - 27 Jun 2010 : 9:47:49 PM
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| Wayne, the cheapest way to get a chamber for your 125, would be to find an old one off a TZ250. There must be quite a few lying about, I might even have one myself. |
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