Topic: Close ratio trans for CB 500/550, can we build one from parts?

[mlinder]

Clear as an azure sky of deepest summer.

It means I have a lot of work to do over the next year.

[bwaller]

 Well if it was too easy it wouldn't be any fun. 

[Howell]

Close ratio gearbox for the CB500:http://www.mpe07.co.uk/
I ordered one by him , special made for the cb500.

This is some conversation by email with Ellis from MPE , he still has 1 cluster for sale.
Hi Rene, yes, lots of progress, all the gears are finished. I am now working on the shafts, they are turned and I will be cutting the splines etc on Monday. If everything goes according to plan it should be finished before the end of the year.
I am making 2 clusters ,so if you know anybody else who may be interested, please feel free to pass the word around.
 
Regards, Ellis.

[kayaker43]

Great resource,.. Can you give us an idea what a full gearbox costs?

[Howell]

Great resource,.. Can you give us an idea what a full gearbox costs?

I would supply the 2 shafts ready assembled with shims ,clips etc, all that would be required is the outer bearings. The cost for this would be £800+p+p.
 
Regards, Ellis.

[lordmoonpie]

Quick technical update on this thread for completeness.....Jaeson Caunce has been in touch and provided some insight into his thoughts on the 6 speed box. Jaeson looked ta this but found that since most of the dog's on the 6 speed are round, the potential for jumping out of gear increases & seeing as the most bullet proof part of the k4 is the gearbox it would only result in building potential failure into the motor.

Jaeson still uses a standard box for racing with a taller fifth gear only. For those that aren't aware of his exploits, he's one of the country's top racers and engineers in K4 Honda racing and is a multi-year champion at the Thundersprint so it can't be that bad a solution to stay with five gears!

[bwaller]

I suppose his comments are intended for my benefit on the CB360 conversion. Indeed the round dogs are a concern, having them undercut is the best we could do. It still is not ready to run so the "jury is still out"!

Thank Jaeson for checking in LMP.

[Sam Green Racing]

I'm surprised Ellis has not commented more on this subject Brent, he did register on here.

Sam.

[bwaller]

I know compared to large block engagement dogs the round type would seem puny in comparison, but there are obviously running 500's with stock gearboxes without trouble.

Sam,  Ellis & I discussed this and he understood that I wouldn't be campaigning this on a world stage  so felt with undercutting it should work well. All the bushings are new and my fingers & toes are crossed!

[oily.tom]

I'm surprised Ellis has not commented more on this subject Brent, he did register on here.

Sam.

Hi, the reason for some of the round dogs being retained in Brent's gearbox was that I was not making a full cluster, only specific gears. I  could not change the dog design on one gear without remaking the mating gears also.
With regard to the std K4 cluster, 1st, 2nd & 3rd are round dogs!

Regards, Ellis.

[DresdaHonda]

OK kayaker, here's the info from CAT

option A - 250 $ - higher 1st + lower 5th - rest of box remains the same.

the new ratios are

1st - 2.176:1
5th - 0.931:1

so from the original box with a 61% span

2.353
1.636
1.269
1.036
0.9

you get a "CR" box with 57% span

2.176
1.636
1.269
1.036
0.931

option B - 1000$ - a totally new gear cluster with true CR - 48.5% span

1.810:1
1.375:1
1.192:1
1.036:1
0.931:1

from my experience with my stock box, the 1.636 2nd gear covers very well the slowest corners, so cant see the advantage of Option A.
Only a slighty higher 1st, you'll never use it in the race. Maybe better starts when you are geared for 110mph @ 12K, say 15:36-15:37 final ratio, at that point stock first is almost useless.

The option B on the other hand sounds really good, the ratios are almost like in the Yoshi 5spd CR. Geared right, 1st would be usable in hairpins and then you'll get that extra ratio for better acceleration. Launches might be hard on the clutch but this is would only be solvable with a 6spd from Nova at 1600$ more.

So: anybody interested? 

TG

To TG
Did you order one ?
-Knowing any using it ? -Is the price still 1000$

Peter


 

[turboguzzi]

No, I didnt, running stock 5-spd.

TG

[DresdaHonda]

With higher 1 and lower 5 ?
-CB650/CB550 Mix ?

Did I understand it right: There have to be a order of some (2,3,4..) complet gearboxes, before CAT the
gonna fabricate ?

-I'm not really ready for that.- BUT i remember some downgearings problems from the past 

Peter

[bwaller]

Contact Ellis at Moore Performance Engineering. He can make you a close ratio 5 spd. Howell is running one in his 500 race bike.

[Sam Green Racing]

The good thing about dealing with Ellis is,  if you have any problems with him, just send me a few £s and I will take a few of my rather large mates round and sort the problem He lives round the corner.

Sam.

[oily.tom]

Ooooeeeerrrr!!! 

[Sam Green Racing]

Ooooeeeerrrr!!! 

Be afraid, be very afraid I bet you talk with a Leigh accent.

Sam.

[Howell]

Contact Ellis at Moore Performance Engineering. He can make you a close ratio 5 spd. Howell is running one in his 500 race bike.

CB500 gearcluster from Ellis:

gearratio's:

1st19/38 2.000:1
2nd 23/34 1.478:1
3rd 26/31 1.192:1
4th 28/29 1.036:1
5th 29/27 .931:1

[Sam Green Racing]

The good thing about dealing with Ellis is,  if you have any problems with him, just send me a few £s and I will take a few of my rather large mates round and sort the problem He lives round the corner.

Sam.

Sorry guys, but with regards to this offer, I'm afraid it's off.(and there was me hopeing to make a few quid)
I just got off the phone to Ellis and he is now my newest best mate cos I want him to make me a new gearbox,   that was the shortest business idea I ever had

Sam, former hit man retired

[bwaller]

Sounds like a better deal anyway.......tough guy.