OzVMX Forum

Marque Remarks => Maico => Topic started by: GMC on April 04, 2011, 09:30:54 pm

Title: HL's are better than Maico's
Post by: GMC on April 04, 2011, 09:30:54 pm

Okay, now that I have your attention ;D

Can anyone tell me when maico changed from the conventional spring mounted exhaust springs to the single large spring over the single long bolt into the barrel?

I thought they started the single spring / bolt on the 79 models.

can anyone confirm please.

Cheers,
Geoff

Title: Re: HL's are better than Maico's
Post by: Mick D on April 04, 2011, 09:48:43 pm

Hi Geoff

The 250, 400, 440 all used the expansion spring type exhaust manifold part#467, on all years up to and including 1980

The 1981 model 400, 440, 490 were changed to bolt on compression spring manifold part#6893.

Except for the 250's which still uses a stretched expansion spring to hold the chamber on, but from 1981 onwards the arrangement was changed to a spigot manifold that is a part of the alloy cylinder casting.

Title: Re: HL's are better than Maico's
Post by: Mick D on April 04, 2011, 09:54:39 pm

68 125 is an expansion spring, although it looks like a handyman conversion ???

69 125 roadie is a bolt and compression spring.

74 MC125 GP is bolt and compression spring.

75 Gs 125 is bolt and compression spring.

Title: Re: HL's are better than Maico's
Post by: GMC on April 04, 2011, 10:11:31 pm

Well I guess the 79 I jigged from had the wrong manifold on the barrel as it was the bolt & compression spring type.
I just had to change a 79 pipe today to the expansion spring type.

Thanks Mick

Title: Re: HL's are better than Maico's
Post by: 250 Magnum on April 04, 2011, 10:24:31 pm

US Maico Service Bulletin dated March 9 1979 states that a bolt and bush has been installed instead of a tension spring on the exhaust. It also gives the engine numbers from where this change will take effect.

Danny 

Title: Re: HL's are better than Maico's
Post by: Mick D on April 04, 2011, 10:41:02 pm

It is a common mod to retro fit the bolt type. It simply is more reliable especially as for as leakage is concerned. The mere fact they made a change shows there was need for improvement. But all factory parts lists support what I have stated.

I would love to add a copy of that Service bulletin amendment to my Maico library, if you wouldn't mind throwing it up please Danny. 

Title: Re: HL's are better than Maico's
Post by: Mick D on April 04, 2011, 11:10:25 pm

All of my part lists are factory and appear identical to these examples in active web addresses.

78 part list (http://www.rageracing.com/Parts/Maico/Yearly%20I.D.%20Pages/78/engine.htm)

79 part list (http://www.rageracing.com/Parts/Maico/Yearly%20I.D.%20Pages/79/engine.htm)

80 part list (http://www.rageracing.com/Parts/Maico/Yearly%20I.D.%20Pages/80/engine.htm)

81 part list (http://www.rageracing.com/Parts/Maico/Yearly%20I.D.%20Pages/81/engine.htm)

All of my engines share the same exhaust flanges as these factory lists.

Title: Re: HL's are better than Maico's
Post by: 250 Magnum on April 05, 2011, 01:24:23 pm

I have a copy of the service bulletin ready to send, PM me with your email address and I will send it to you.

I would post it here but it is far easier to split the atom than it is to put a photo on this site.

Danny

Title: Re: HL's are better than Maico's
Post by: GMC on April 05, 2011, 02:39:37 pm

Thanks for your help guys.
I guess the question needs to be asked of the customer everytime I build a pipe for these models.

Quote from: 250 Magnum on April 05, 2011, 01:24:23 pm

I would post it here but it is far easier to split the atom than it is to put a photo on this site.

Check this out

http://ozvmx.com/community/index.php?topic=17785.0

Title: Re: HL's are better than Maico's
Post by: TM BILL on April 05, 2011, 03:13:36 pm

Quote from: 250 Magnum on April 05, 2011, 01:24:23 pm

I have a copy of the service bulletin ready to send, PM me with your email address and I will send it to you.

I would post it here but it is far easier to split the atom than it is to put a photo on this site.

Danny

Splitting the atoms easy  ;) just send it through the post marked FRAGILE PLEASE DONT BEND  ;D

Title: Re: HL's are better than Maico's
Post by: Canam370 on April 05, 2011, 03:24:56 pm

Splitting the atoms easy  Wink just send it through the post marked FRAGILE PLEASE DONT BEND  Grin

 :D

Title: Re: HL's are better than Maico's
Post by: Mick D on April 05, 2011, 05:23:08 pm

Quote from: 250 Magnum on April 05, 2011, 01:24:23 pm

I have a copy of the service bulletin ready to send, PM me with your email address and I will send it to you.

I would post it here but it is far easier to split the atom than it is to put a photo on this site.

Danny

 :D :D :D

Great stuff Danny, I will send that PM now, cheers.

Title: Re: HL's are better than Maico's
Post by: Mick D on April 06, 2011, 04:36:53 pm

Quote from: 250 Magnum on April 05, 2011, 01:24:23 pm

I have a copy of the service bulletin ready to send, PM me with your email address and I will send it to you.

I would post it here but it is far easier to split the atom than it is to put a photo on this site.

Danny

Thanks Danny, I nearly went insane last night, it wouldn't upload to Photo-bucket ???

In the sober light of today, It finally dawned on me that the file was too large in megabyte size.
I finally figured how to reduce it, and Bingo ;D

(http://i677.photobucket.com/albums/vv132/mc125mick/Maico_Service_Bulletin_3-79.jpg?t=1302071089)

They say if you learn something everyday, it should be  a good day.
Got me stuffed, but thanks for the education Danny and addition to my library.

Quote from: GMC on April 05, 2011, 02:39:37 pm

Thanks for your help guys.
I guess the question needs to be asked of the customer everytime I build a pipe for these models.

[/quote]

Cheers, Mick.



 

Title: Re: HL's are better than Maico's
Post by: Mick D on April 06, 2011, 04:59:49 pm

This time I have printed it and the shot it with the camera a couple of times, that's the quickest and best I can do, no more. I WILL be needing a Valium or something now.

(http://i677.photobucket.com/albums/vv132/mc125mick/FORUM227.jpg?t=1302072796)

(http://i677.photobucket.com/albums/vv132/mc125mick/FORUM226.jpg?t=1302072864)

Title: Re: HL's are better than Maico's
Post by: 250 Magnum on April 09, 2011, 12:02:52 am

No Worries Mick, sorry about the big file size, next time I will try saving it as a PDF file and see if that makes it easier to handle.

Danny