aybe some previously used for drag racing Heads on a bike Built to Flip??
Who knows ? You know how these old bikes are. I got it fairly cheap with all this so called race stuff on it. I'm just trying to put it back on the road. Nothing fancy, just a good running bike.
Apparently the front guides come with a ring that goes in a groove.
Exhaust guide on left is a Rowe 80" 5101-03 Cast Iron
Intake guide on right is a Rowe 80" 5100-03 Cast Iron
Just a note. The cast iron guides were still a nice fit. The nickle bronze ones were a bit loose. Two different types of guides. Must ba a racing thing.
No..Probably two different type Valves were used...I'm gonna guess Stainless in the Cast Guides, and a hard valve...good old steel maybe or something exotic, in the Bronze.
If the new guides go in easy...you are asking for trouble...
we always pulled old guides, paying close attention to effort/force required, measured carefully, and sized new guides accordingly..My Partner was fanatical about Inside Ream and Finish as well....All that on Street Bikes...I won't go into Race Bike just now..
No..Probably two different type Valves were used...I'm gonna guess Stainless in the Cast Guides, and a hard valve...good old steel maybe or something exotic, in the Bronze.
If the new guides go in easy...you are asking for trouble...
we always pulled old guides, paying close attention to effort/force required, measured carefully, and sized new guides accordingly..My Partner was fanatical about Inside Ream and Finish as well....All that on Street Bikes...I won't go into Race Bike just now..
Trust me, with that one loose guide, I'm going to checking those holes or bores very carefully.
I'll post some pictures of the chambers and ports. I think the heads have been ported. Plus somebody kind of marked up the areas around the valve seats. Looks like they didn't know what they were doing. I always just take an old valve and tack weld it to the old guides. They pop right out. (Well, most of the time.) These look like they were dug out. UGH. Looking at the bike overall, I think this thing was cobbled together with anything they could find.
A lot of swap meet specials were slapped together by people looking to cash in on the yuppie & european buyers that was going round heavily in the late 80's & 90's. That aside you get to looking at all the odd ball stuff that was done to yours it's testament to how durable and forgiving shovel are, friggen twinkie wouldn't handle it.
A lot of swap meet specials were slapped together by people looking to cash in on the yuppie & european buyers that was going round heavily in the late 80's & 90's. That aside you get to looking at all the odd ball stuff that was done to yours it's testament to how durable and forgiving shovel are, friggen twinkie wouldn't handle it.
The story on this bike was that it was a drag racer. I was told other things too but after dissecting this thing, none of the stories pan out.
When I'm done, it will be a good running machine
I grew up in the era of the Shovel. I was in first grade when the first ones came out and I was 25 when they quit making them. I was 28 when I got my first one. I like other models too but my favorite will always be the Shovel. Easy to tune, easy to maintain, and fairly easy to ride. They are indeed tough.
When I was younger, I worked in a small machine shop. One of the the things I was taught was if you are having a hard time nailing down a measurement, take several and see what the number is that comes up most of the time. Now this doesn't always work in every situation, but for the purposes of measuring the bores for the the valve guides, I came up with these numbers.
Front Intake .630"
Front Exhaust .631"
Rear Intake .627"
Rear Exhaust .632"
The removed guides O.D. are:
Front Intake .633"
Front Exhaust .633"
Rear Intake .629"
Rear Exhaust .630"
The front head with the cast iron guides was in decent shape. The guides were both of the same type and manufacture. The valves still fit well with the "wiggle test". The exhaust valve being stainless.
With the rear head, the numbers tell the story. The nickle bronze intake guide was in place pretty good but came out easier than the cast iron ones did. As mentioned earlier, I could almost pull the bronze exhaust guide out with my fingers. With the hole being .002 over the size of the guide, you can see why. Makes me wonder what happened here.
Anyway, I have to determine what size and type the replacement guides will be. I've been told and read that you go up to the next size. However, after measuring the holes in the head, it makes me question about routine sizing of these guides.
Sorry...we did it by feel as well as measurement...No Help.
My easy and yours may vary significantly...and our procedure was always to cook the head to a specific temp...which I don't recall just now.
05-29-2016, 12:15 PM
