880 Dreer tribute bike update

grandpaul

VIP MEMBER
Joined
Jan 15, 2008
Messages
12,146
Country flag
I was going to post this as an update to my original build thread, but even scrolling thru the entire rebuilds section, I can't find that thread. So, here is the update:

After building up the original Dreer prototype, I stayed in touch with Kenny and bought a bunch more VR880 stuff from him, including bodywork. Then, after several other build projects, I had a spare frame and engine parts, so I built a 2nd, then a 3rd VR880 replica. This one is a '74 880 with a Yamaha XS650 front end and a Honda CB750 rear wheel, with a VR880 box section swingarm on big bearings. After I finished it, I decided to have Tom Reid install the Spyke starter Kenny sold me when I was building the prototype bike. That took nearly a year. Once i got it back together, the e-starter worked amazingly well, but after the 2nd or 3rd test ride, it started making crunchy noises. It got parked due to an overloaded work schedule, then in 2019 we moved up here to central Texas (Leander) and it sat in storage until last year. In November, I broke my leg in my first at-fault accident in 47 years of riding; not having medical insurance necessitated selling off a few bikes to pay off the hospital/doctor bills. Among the bikes sold was this '74 880, with the understanding that it would be sorted and ready to ride. So, once my leg was up to moving around, I got after it...

First order of business was to check for a stray pushrod or rocker adjuster - no joy.
IMG_8139.JPG


Second, check the primary for something amiss - no joy.
IMG_8141.JPG


Next, fire up the wifi endoscope and have a look inside the cylinders- Houston, we have a problem.
IMG_8268.JPG


I didn't recognize what this might have been, so the head had to come off-
IMG_8272.JPG


Once the head was off, the cause was evident- a broken intake valve guide.
IMG_8274.JPG
 

grandpaul

VIP MEMBER
Joined
Jan 15, 2008
Messages
12,146
Country flag
The seats looked ok, but some of the broken bits "smeared" the alloy of the head over a bit too close, and there were several nicks with sharp edges, so off to find a new machine shop...
IMG_8319.JPG


The offending bit...
IMG_8320.JPG


You can't tell from any photo, but it was easy to see the tiny crack of light coming through the valve seat, didn't even need to check them with a dial indicator, both valves were bent. FANG.

Took 8 phone calls to finally find a machine shop in the area that handled bike stuff, this one is EXCLUSIVELY bike stuff, and the guy custom builds stuff for his son's IHRA drag bike racing effort. So, I took him the head with the new pair of valves and guides from Fred & Ella.
IMG_8321.JPG


Since the buyer was going to have to wait longer than anticipated, I decided to treat him to new tires...
IMG_8308.JPG


Pretty serious-looking at this point...
 

grandpaul

VIP MEMBER
Joined
Jan 15, 2008
Messages
12,146
Country flag
"What came first, the chicken or the egg?"

In this case, I'm fairly certain the guide failed first. The valves chewing on the bits caused them to get bent.

What caused the guide to fail? THAT, I don't know...
 

grandpaul

VIP MEMBER
Joined
Jan 15, 2008
Messages
12,146
Country flag
The machinist cleaned up the head in his mill, and smoothed off the rough spots on the combustion chamber. He said the seats cleaned up fine and produced a nice clean mating ring of machinist's blue.

IMG_8597.JPG


Avons took a little longer than usual to get mounted, the shop owner retired and his son is running the show now. I think he's doing a lot of OJT with his buddies as employees...
IMG_8369.JPG


I used the "bit of rag" technique to drop the head in place - one go, and done.

IMG_8599.JPG
 

grandpaul

VIP MEMBER
Joined
Jan 15, 2008
Messages
12,146
Country flag
I spent a while cleaning all the nooks and crannies of the bike, it's been moved from sitting in my old garage, to sitting in a damp storage building, to sitting in my new shop for almost two years.

Spent a couple of hours rebuilding the less than 100 mile old Brembo front master cylinder, then bleeding the front brake. Looks like it might be weeping at the tiny plastic fitting that connects the reservoir hose to the MC body. Dang...

(no photos of the above, sorry)

Cursory photo of the engine back together, and rotating smoothly with kickstarter...
IMG_8601.JPG
 

grandpaul

VIP MEMBER
Joined
Jan 15, 2008
Messages
12,146
Country flag
So, yesterday morning the time came to finish the basic services and go for the start-up.

First obstacle - the new AGM battery was not fully charged (my fault). Connected the charger unit, double-checked all the wiring, then punched the button - click, click, poof (blown fuse). Kicked it through then decided to take the plugs out; click, click, poof. Started looking around and found the solenoid trigger wire had been pinched between the solenoid cover and the transmission cradle (awfully tight fit). Loosened off the trans top bolt and the engine top/rear bolt, wedged a screwdriver between the trans case and the cradle top, giving me JUST enough freedom to gently push the wire clear. Replaced fuse, pressed button, WHIR WHIR, WHIR!

Plugs back in, caps back on, push the button, WHIR WHIR, WHIR (with no start). DOH! Installed the sidecover that has the Sparx brain fastened to it, connected the connector, depressed the ticklers, no fuel weep. Disconnected the fuel lines, turned the taps on - no fuel flow. Crud (literally). Took a while to pull the brand new petcocks, only to discover the small amount of fuel that was left in the tank years ago, was more than enough to DESTROY the cheap plastic petcock filter screens, and gum up the entire works. Actually a good thing they didn't flow, or the gunk would've gotten to and thru the carbs.

Got the petcocks clean, then swooshed the gallon of gas I had poured in the tank till I thought the residue was dissolved. Dumped it, poured in another 1/2 gallon, sloshed it around really well, and it came out relatively clear. Did another 1/2 gallon and was satisfied it was clean, put it all back together and pushed the button click click click click NUTHIN. Took a screwdriver handle and tapped the solenoind cap a few times, pushed the button - VROOM! ...but no idle.

I'm 99% sure the brand new Amal Premiers are also gummed up. DANG. What a pitiful sight...

IMG_8603.JPG
 
Joined
Apr 22, 2020
Messages
954
Country flag
Good to know about the modern fuels dissolving the white plastic filters in a stored fuel tank. I might install a couple of 40 micron -6 AN fuel filters in the fuel lines. EFI hose seems to be OK with the modern fuels. If I were industrious, I'd build up PTFE fuel lines. But I digress

Since this thread was started in the builds section, I'm going to pretend it is open for discussion.

What were the mechanical design challenges you faced installing the Yamaha front end and Honda(?) swing arm?
 

grandpaul

VIP MEMBER
Joined
Jan 15, 2008
Messages
12,146
Country flag
What were the mechanical design challenges you faced installing the Yamaha front end and Honda(?) swing arm?
Near zero up front. The yoke stem needed 2 minutes in a lathe to fit thru the Norton steering bearings.

The rear is a Kenny Dreer VR880 box section/big bearing frame that came to me without axle bosses / chain adjusters. Since I had full access to my custom knifemaker's shop, it wasn't significantly hard to fab everything up. I designed the bits in AutoCad and they worked a treat, as they should (that's them sat on the plywood deck of the bike lift in a previous photo). I had at least a dozen different rear axles, and one of them fit just right, with a fiddly inner spacer needed to keep the brake plate hub away from the drum face. The big bearing swingarms use standard Norton steering neck bearings.

I happened to have the cool brake torque arm from some dirt bike, and I managed to fit up with just some trimming and fitting, re-trimming and re-fitting, till it fit. I used the last slot near the brake hub to mount a custom-made brake cable abutment thru. I had it polished, looks nifty.

One of these days, I'll re-post the entire build...
 
Last edited:
Joined
Apr 22, 2020
Messages
954
Country flag
Thanks for the info.

For a simple front end swap, the best thing I could do is find a complete set of 35mm stanchion tube forks with at least one disc all in good order. The Yamaha setup as well as others would probably work. Finding good clean parts is the challenge for me there. And motivation to follow through.

I was afraid that swing arm setup you put together would be unobtanium. My fabrication skills are limited to hand drills, a dremel, hacksaw, files, drill press, 6 inch vice, and bench grinder. No machine shop.

Ran into some of your old posts out there in the ether about these mods. Very :cool: !!
 

grandpaul

VIP MEMBER
Joined
Jan 15, 2008
Messages
12,146
Country flag
It didn't happen all at once, but once I gave Kenny Dreer almost the same amount as having him build me an 880, I was able to re-sell a lot of the parts at a fair profit, which helped backwards-finance the other two builds I did. Pretty fun making stuff, especially when it works fairly well!
 
Joined
Apr 22, 2020
Messages
954
Country flag
Working with one's hands and brain is very satisfying. I spend countless hours doing stuff I could let somebody else do in half the time, but since I have no real social skills, it's better that I do as much of the work as possible. ;)
 

grandpaul

VIP MEMBER
Joined
Jan 15, 2008
Messages
12,146
Country flag
Sure enough, the carb bowls were a mess...
IMG_8630.JPG


Got them cleaned up and the bike started fine, but was idling high. Took a few minutes to figure out that the throttle cable had been pulled out of the splitter tube and was hanging! Got is sorted and it's running decently, idling ok. (day before yesterday)

Today's order of business was to get out for a test ride! The fun began when backing the bike down the steep ramp (I had no idea what I was doing when I formed and poured it in place, it's WAY too steep). I crept down slowly (backwards) hand on the front brake lever, but as the front tire got to the rubber mats, it took off skidding! Thankfully, I kept it right-side-up.

Fired it up and went to shift it into first and realized my right foot/ankle is on NO CONDITION to do that with the rearsets. So, I reached up with the back of my heel to get it into first, and rode off. Took a spin up the road and back about 50MPH top speed just taking it nice any easy up and down thru the gears to let the rings bed in (NO NEED for break-in method discussion), felt GREAT! "Zippy". The turn-around was iffy, front tire is low (have to see if its just low, or they punched the tube installing it). Otherwise the test ride was uneventful and successful.

Parked the bike in the hangar and let it cool off while I started working on the hangar door wheel brackets. Came back an hour later and not one drop of oil to be seen anywhere. Success #2 for the day.
IMG_8634.JPG
 
Top