1974 Maico 450 Build

[flyingdg]

GMC, Thanks for the info on the frame. I added your post to the Blog ( I hope that is OK ) I think there could have been three types, the straight inside top bracket, the one bent like yours, and the one with holes. Thanks DG

[GMC]

GMC, Thanks for the info on the frame. I added your post to the Blog ( I hope that is OK )

Yeah, no probs.

I did hear somewhere once that there were 3 types of shock mounts, but I have only seen 2 types myself.
Didn't know what the 3rd was, wasn't much different then if it was only that inner mount that was different.

[paul]

http://www.vintagemaicos.com/74.5info.htm

[flyingdg]

Paul, Geoff, Thanks for the info on the GP frame! Geoff I also added a link to your site. Very cool stuff! I really like the GP repair kit. Do you also sell a repair kit for the standard frame?

[GMC]

Do you also sell a repair kit for the standard frame?

I'm actually about to put one together for someone in the next couple of days.
It will go on my site soon too.

[Tahitian_Red]

Since we are talking Maico frames, which would be the best choice to build up a GP racer?

1. 73 frame with GP updates
2. 74.5 GP frame
3. 75 frame (legal as 74.5 replacement here in the US)

I've always wanted to build one for racing and Doug has me inspired with his blog. 

[Husky500evo]

     If it is legal to use where you are, then the '75 frame is probably the best option because it is a stronger/safer frame. On the '75 frame the two front down tubes wrap around the front of the steering head tube. I think they did this because the '74 frames had a habit of snapping the headstock off when landing off big jumps. Just be aware that the '75 frame is wider where the swingarm fits in, to accomodate the 5 speed motor, so you may have to make spacers for the sprockets to line up when you use a 4 speed motor . Also the '75 frame has tapered roller steering head bearings, so you would have to use the longer '75 stem with the '74 triple clamps (the '75 clamps suit the bigger diameter fork tubes).
     Alternatively, GMC does a weld on gusset plate mod that wraps around the steering head on the '74 and earlier frames, which is what Wheelsmith did back in the day .   

[flyingdg]

I got some more posts up on the Blog. New Aluminum front fork spring cups and a new ignition. DG

http://1974maicogp450.blogspot.com/

[flyingdg]

Sorry I'm so slow on this build! But I do have some new posts. DG
http://1974maicogp450.blogspot.com/

[firko]

It's a pity there's no words DG as the photo's show that you're meticulously following many of the tried and true Maico tricks of the trade . It's interesting to see that you're using a Magnum style squish head. I've been using that style of head for a long time, even on my square barrel and find that it works so much better. I see you've gone to a lot of trouble polishing and getting the clutch just right but did you consider using a Magnum style clutch?
I reckon that a lot of Maicos clutch problems comes from the welded early clutch basket flexing under load. The billet later basket doesn't flex at all, helping quite a lot in freeing up the action. Since I swapped over I've had zero clutch problems. My next experiment is to try one of those Maicos Only 'Wheelsmith' style coil spring conversions.

[flyingdg]

Firko
I'm not much on words, but if you click on the photos there is some. The basket on the Mag. bikes are a lot better than the older one with the ring. But I think the problem is in the flex of the pressure plate or clutch guide plate, with the stiffing ring i make welded on the guide plate the clutch works a lot better. There is a you tube video on there that I put a big clutch in a 450GP and I make a single ring hub and have a ring welded on the clutch guide, I also make a taller push pin. The clutch worked great. The video sucked but the clutch worked. DG

[vmx42]

Do you also sell a repair kit for the standard frame?

I'm actually about to put one together for someone in the next couple of days.
It will go on my site soon too.

What type of steel are you using Geoff?   








_{Come on, you knew somebody would ask!!!!}

[flyingdg]

I have a question about the baskets flexing. I have heard that before about  the older baskets with the ring around it flexing, I just can’t see how it can flex. All the energy is in the center hub, guide plate and terminal plate. The basket is only holding the plates in line. The thing I see is the older basket is softer and groves easier than the new  and harder Mag. Basket with out the ring. So my question is how can it flex? I ask this with respect, I just can’t see it. Thanks DG
Here is a link to the you tube video I did and what I think is going on  in the clutch. Sorry about the video it was my first time.
 http://www.youtube.com/watch?v=Ppk-2CZOsI4&feature=relmfu

[GMC]

Do you also sell a repair kit for the standard frame?

I'm actually about to put one together for someone in the next couple of days.
It will go on my site soon too.

What type of steel are you using Geoff?   








_{Come on, you knew somebody would ask!!!!}

Carbon 0.30 %
Manganese 0.90 %
Silicon 0.30 %
Sulphur 0.030 %
Phosphorus 0.035 %
Chromium 1.10 %
Molybdenum 0.25 %
Iron - Balance



Shit. I still haven't put those bits on my site yet

[flyingdg]

There is some more updates on the GP 440 build. DG
http://1974maicogp450.blogspot.com/