69 CAT 300 Rebuild

#1
Well Gents, been awhile since I have been on here. Have had this mini bike for 25-30 years now and the kids rode it 1000's of times as they grew up. They are long gone from the house now. It's been sitting in the shed for many years now so giving it a face lift. Not trying to restore it as "original", just repaint and replace some parts.

Motor is not original as it is a B&S 3.5 I bought about 25 years ago which runs fine. Forks are, I believe, from a Nova. Seat is not original

Few ?'s

What color were the 69 CAT 300's (orange like a Hugger orange)?

How would I remove the fork springs (pic)?

Clutch is a 5/8" x 12 tooth. It rattled quite a bit at idle but did work. The whole inside just "fell" out as a unit when I removed it. What is a decent brand to get? I see tons online

The clutch mounts on shaft sprocket in towards motor

It appears PO removed what I think were metal plate straps welded across the top of frame ( PIC I see weld marks). I wanted to buy some bar stock and cut/shape 2 pieces and drill a hole in each to then secure the seat. Was going to go to a muffler shop and see if the guy would do it for $20, ideally less. I don't have a welder and would prefer not to drill/rivet them in place unless anyone feels that would be "OK".

I had previously cut a piece of 3/8" plywood the shape of seat I screwed to the bottom of the seat and had a bolt/clamp kind of attachment that works but I wanted to do it more the way these were made. The material in the bottom of the seat is fairly thin so not sure if it by itself is good enough to screw into or the seat needs the plywood between it and frame. I have the seat over hanging the back of frame so the plywood base seems to support it. I see over the years the rear of that plywood is slightly bend down some (to many grown up riding it back when :)

Going to rattle can the frame. The wheels are not original and are aluminum. Was going to buy some "aluminum" paint color and freshen those up.

Bought a new throttle & 52" cable as the one now is very hard plastic and not that comfortable + it is at least 30 year old.

Foot beg covers I see are available through the warehouse. I would have to cut them down as my pegs are 7/8" x 3" and these are 4.5" but that should be no big deal

Anyway I would appreciate some comments and suggestions and I will post pics as I move ahead with it
 

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#3
My Hilliard 5/8" clutch sheared the key from the clutch hub. It still worked but did vibrate during acceleration and "rattled" during idle.

Not sure I want to get another Hilliard or Max Torque

Motor is 3.5 B&S

Gearing is 12/68 with a 12" tire

No damage to engine shaft
 

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#4
If that is only the drive hub that is bad, Hilliard # 8444-23-062C should be a 5/8" replacement drive hub, and cost less than $9.

Found here: 5/8 Inch Drive Hub - Recreational Motorsports

Cat used "Competition Orange" which was a 70's era Ford orange paint code. No idea if it's available in rattle can.

Pegs were 3/4" originally, but you can cut down rubber/plastic as required.

You definitely want that seat to be anchored with welded straps as original. Alternative would be holes in the frame, but it would weaken it I think.

Seat bases should be 1/2 at least, and yes, on those shorter bikes, seat overhang and adult riders equals "sag." T bolts are used on those, inserted and measured with the frame before upholstering of course. 1/4-20 on this one.

Engine mount/base is swiss cheese. With that small engine, you're probably okay as long as you use large washers on the bottom when you mount the engine with 5/16 grade 5 bolts.

Several of us on here are very familiar with these bikes. My (now deceased) son had one when he was 8- about 1982, when we lived in SoCal. It was orange as well, and sported a smaller Briggs.

Sounds like you know what is required here. You could restore that, but as Rooster said, you pretty much have a running bike now.
 
#5
If that is only the drive hub that is bad, Hilliard # 8444-23-062C should be a 5/8" replacement drive hub, and cost less than $9.

Found here: 5/8 Inch Drive Hub - Recreational Motorsports

Cat used "Competition Orange" which was a 70's era Ford orange paint code. No idea if it's available in rattle can.

Pegs were 3/4" originally, but you can cut down rubber/plastic as required.
Really appreciate the link for the hub. Way cheaper than a $45 clutch. Looks like I just need to pull the "C" springs and transfer the clutch ears over. The clutch otherwise looks OK. Never oiled it but will before it goes back on

The pegs are 7/8" OD and use a 3" peg sleeve. IDK if they are "stock" but appear to be. Would like to find a sleeve in 3" but could cut down a longer one.

IDK if the brake foot lever had a rubber cover also or not. It looks to be 1/2". Maybe a motorcycle foot shift would fit?

Yeah the motor plate is swiss cheese. I made 2 x 1" metal flat bar that bolts to the rear of the floor plate and is drilled specific to the B&S 3.5. I use grade 8 fender washers on the bottom side so the engine is mounted securely

Will make a new plywood base plate for the seat and screw it on. I put on 3/4" bar stock across the top of frame in 2 places to secure the seat

Fork springs actually cleaned up pretty good under my bench wire wheel as did many of the other parts.

Front Mag rim is Al so it wire brushed up pretty good and some rattle can will clean up rear rim/sprocket

My throttle is at least 30 years old. Works but I bought this to swap it and the L grip out.
https://www.amazon.com/gp/product/B00HSWDQQS/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1

The MB was running when I stored it last. Had run the tank empty. Oil is nice and amber color

Hit the motor with some black engine paint to freshen it up

Comments appreciated
 
#6
The pegs do look stock. If they are stock, they are 3/4" If they are 7/8, they are an excellent reproduction.

BSA shifter peg fits right on the end of that scrub brake. https://www.ebay.com/itm/BSA-A7-A10...461559?hash=item3a8baccfb7:g:TaUAAMXQlgtS~oVJ

I've always purchased OldMiniBikes's throttle cable set. Not only does it look better, it is more comfortable, and mini bike correct, although it does cost a little more.

There was an OldMiniBikes member selling front forks for that bike, but the forks that are on it almost look like modified Cat forks with a lower spring added. Someone here knows what front end that it. The rake looks off to me from the photos. If it were me, I'd try and get it back to original, but it's yours. :)

If you do decide to get the front end back to original, these wheels are Cat outters, with a CNC inner that runs very true. Better than original, with original looks.
 
#7
There is nothing original "CAT" other than the frame. Not going to buy all "CAT" stuff to make it original. It served well as the kids mini when I bought it and became my "pit bike" at the drag strip for years. The handle bars un-bolt so I could fit it in the trunk. It's just going to be a neighborhood put put now. I have some free time so just giving it a face lift. May wind up selling it later

I have the "OldMiniBikes" type throttle now although it is very old. Hard plastic grips. The Amazon one is cheap and if it is a POS I will get one from OldMiniBikes

Thanks for the BSA peg link. I was going to Google motor cycle peg sleeves and see what comes up.

You are right, foot pegs are 3/4". Will look for 3/4" x 3" covers

I was ordering that Hilliard clutch part but after 13.99 shipping and $5 handling the $28 was getting tall. On closer inspection the 12 tooth gear had the tips of the gears bending so by the time I add up $ for those 2 parts + shipping & handling I bought a new Hilliard for $42

I did find some "Competition Orange" spray paint so at least will be period correct on color:)

I have some new #35 chain and new link to make a new chain I found from the previous time I bought parts years ago.. Also had a wheel bearing as the "drive" side one on rear wheel was rough

Appreciate all the tips & leads
 
#9
There is nothing original "CAT" other than the frame. Not going to buy all "CAT" stuff to make it original.
Well, I was responding to a thread entitled "Rebuild" and figured you were interested in making it correct. I looks to me like your rake is incorrect with that short Nova front end.

Here are the correct foot peg covers.

The BSA covers: I don't recall trimming the BSA covers, so if I did, it wasn't much of an issue. I also used contact cement on them.

Here's a couple of 250's, one I am modifying obviously, compared to an original one. Note brake lever. That is a BSA.



Here's my eldest several years ago riding his 300X when we lived in SoCal. He passed recently, but this was his first bike, among a long list of bikes he owned all over the world.

Joe on Cat 1982.jpg
 
#10
Yep I should have titled "refresh" vs "rebuild" or "face lift" :)

I know my forks are not CAT, assume Nova. The tube they attach to though is on frame so the rake would, to me, be the same as it appears the CAT forks are straight (not a bend in them) as is my forks.

My foot brake is likely bent up some as yours appears to sit closer to frame and the foot rest part is straight where mine is bent back some. There is a Harley dealership a mile from my house. Going to check out what they have for shifter/brake sleeves. Looking at this part #:

Harley-Davidson® P/N 33189-63T

I think my rear rim is CAT since it looks like yours. Front rim I have IDK what its from

Condolences on your Sons passing.
 
#11
Cleaning the frame up for paint and cut off the old peg covers.....it would appear the original color was yellow unless a PO painted it.

IDK if CAT used yellow and if so for what years or model. I thought my frame was a 300??

Serial # is 943543
 

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#12
Yes, that yellow was used on Cats. In the brochures and historically, we know that the 300TT came in that color. We also know that the brochures are not the "be all, end all" authority on what went out the door. But yes, yellow was used.

The 300 series used a small spring in the front end, just below the neck. The neck was thus shorter than the necks of the 250 series. I can tell you the 250 series used a 6" long neck. So if yours is shorter, it might be a 300. Then again, with that Nova front end, someone could have cut that neck to fit the bars. And yes, your rear wheel is Cat.

That front end (spring or no spring) was the only difference between the 250 and 300 variants. Also, the 300 series came with the detachable wheel stars. I didn't see any on yours, but they could have been removed and discarded.

The serial number makes yours a 1969, and one of the only ones I've seen with a recessed area for the kick stand mount.
 
#13
The neck tube for forks is 5". If it was cut it was done very cleanly but I see no witness marks suggesting it was.

I made the seat flat bar stock mounts and got them on. Took a propane torch to the scuff brake arm and a BFH to bring it back closer to frame. It had been bent out

Going to make some modified "L" brackets so I can position the seat far enough back for "grown ups" and give the rear seat some support

I did order the peg covers you had a link to from the ebay seller. Going to swing by the Harley shop to see if they have what I think will work for the scuff brake peg. If no luck there I will get the BSA one

Wish I had the fab skills and welding ability you have. Saw your thread on the swing arm mod. Very cool mod.

I just have hand tools/drill/sabre saw, bench vise and grinder
 
#14
Here is the seat bracket mock-up

Used 2" "L" brackets I cut/modified for the rear seat bracket. Holes were already drilled into frame. IDK if they were previously for something like this or if CAT had something (fender attached to the holes??)

I am 6' 2" so need the seat back further than stock

On to paint now and parts will be showing up in the next week to put it all back together again
 

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#15
Fresh out of paint and now it rolls!

It's the 4th color on it since I got this about 25 years ago. Got it Black then Red, Dk. Purple and now "Competition-Hugger-Hot Rod Orange"

Waiting for some parts to come and have flat bar to bridge the swiss cheese engine plate. Its the way I got this. The flat bar on top and fender washers under hold the engine just fine

Now I can position the seat with the new rear extension brackets I made and pre-drill the seat base.
 

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#16
Got these foot peg covers on ebay

http://rover.ebay.com/rover/1/711-5...0001&campid=5335845805&icep_item=173542196499

My pegs are 3" and I find I ride somewhat "pigeon toe" to keep my feet on. Yeah these MB were built for kids


I added 1" length to the pegs and then cut about 1/2" off these peg covers

I found some 1/2" OD stainless tubing that with just 1 wrap of Gaff tape fit "snug" inside the peg. I then wrapped 1" width of Gaff tape around the end to build it up to 3/4". Peg sleeve fit snig over and I think the "wider" foot peg will make for more comfortable riding
 

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#18

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