Friday, November 21, 2014

Honda GL1000 Single Carb Conversion?

We've been at our Winter retreat for 10 days already. Been working on minor projects....cleaning up the yard and some RV repairs which have stacked up over the past 9 months.
Finally took a little time and removed the Gold Wing carburetors. Prior to removing them I performed a compression test on the engine....PSI ranged from 139 psi to 142 psi across the 4 cylinders....sign of a perfectly healthy engine.
 The OEM carbs have caused me minor problems for the past 3 years and have never worked as they should. If the bike sat for more than 2 weeks it would flood and not want to run, usually flooding and gas would expell through the exhaust manifold. After a thorough warm up the bike would then run, but never as good as I thought it should. I got into the habit of starting the bike once each week and warming it up to riding temperature, even if I wasn't riding it. This weekly procedure at least kept the bike ready to ride. But last August it basically "died" on me, not getting fuel to the right cylinders at lower RPMS....engine would run at 4000 RPM's and higher but not in the lower ranges.

 I have a few different options:
1) Rebuild them myself.....this option would be the best. A rebuild kit from "Randakk" runs about $189.00. But the 4 top plastic "plugs" in the top covers have rotted and one had a hole in it last Winter which I jury rigged a fix. I cannot find any replacement parts for these so I'd need to buy a set of 4 donor carbs to replace the top of each CV chamber.  Also I don't have the equipment to properly "soak" them to clean them out. I simply did not want to tear into the complex "4 carb" rack. Once mounted on the bike the multiple adjustment screws are nearly impossible to access. I attempted to remove the bowl drain plugs last Fall....no way to get the soft brass plug screws loose without stripping them. The OEM design is definitely the best, but overly complex and difficult to keep working properly.
2) I had a quote for a rebuild from a retired Honda mechanic....quote was for $850.00 to rebuild / tune the bike. Way more than I am willing to spend. A local shop would rebuild them if I brought them in...cost of rebuild kit plus 3 - 4 hours labor. Likely a total of $500.00 - $600.00 by the time it was done.
3) Go to a more simple alternate carburetion. After many hours of research I found multiple different bolt on options:
        This set up utilizing a "Solex" type one barrel carb sells for around $400.00. I don't like to looks of the squared plenum, I would think that fuel mixture flow would be disrupted.
 This bolt up set up about the same...same carb and slightly better manifold.....$400.00.

This design appeared to be the best...again with the VW one barrel carb and a better designed intake....$580.00


After more research I just don't think the Solex one barrel carb would be sufficient to handle all ranges for the Gold Wing. Read a lot on the subject.... many have installed and like the above set ups.

I finally decided to go a different route and ordered the items below today. This will require some design of my own and won't be a "bolt on and go" scenario, but talking with folks who have built / used them, I think it will be an easier option rather than  maintaining the more complex OEM system. Also should be a better fit for the ranges needed for highway / street riding than the Solex single barrel carb. I found some information from a guy on the Internet who has done this exact conversion. Trying to follow his "lead" as close as I can. He put a lot of effort into research / developement while designing his conversion. 

                VW Type 4 Bus engine Plenum.......

            Weber "32DFT" 2 barrel carb using a progressive (linkage operated) secondary.

My experience with the Weber carbs has been excellent over the years. I once replaced a troublesome Solex 2 barrel with a Weber 2 barrel on a German car I had years back. The Weber was much better and trouble free.
I will need to come up with either piping or tubing to connect the plenum to the heads. The stock intakes which attach to the heads will be retained and used. I've also purchased a "universal" throttle linkage kit which will allow used of the OEM throttle cable. This project will require a bit more labor to install but I think the final installation will be much easier to maintain and tune than the OEM setup once everything is dialed in. Hopefully I won't regret this decision....Discussing the above set up with folks who have toyed with the single carb conversion, I found that the chosen setup should be the best alternate to the OEM system...we'll see.....

UPDATE:
Slowly acquiring required parts. The manifold / linkage / air cleaner assemblies arrived. The Weber carb was finally shipped earlier this week. Ended up that the carb vendor was on vacation for a couple weeks so shipping was delayed until this week.
Went out yesterday and found some fuel "friendly"  1 1/2" intake hose. Decided to attached directly to the intake manifolds with the fuel hose. That required removing the rubber intake attachments on the OEM manifolds. I did not realize the rubber was perminantly bonded to the intake alloy manifold. I damaged the first one to remove it. The "lip" on the OEM manifold (which the new fuel runner attaches to)  is quite small. Hopefully I can acheive a positive seal with clamps. I'll go ahead and strip the rubber off of the three remaining manifolds today. Others use a rigid pipe (of different types) and retain the OEM manifold / rubber. If my technique fails, I went ahead and ordered a replacement set of used OEM manifolds ($18.00 for 4 with free shipping.)
I found another design where as folks are making single carb manifolds out of sch. 40 PVC pipe with reported success. They use single barrell VW carbs though, which I decided to avoid.
Slowly but surely I'm gaining some progress. If all goes well I should have everything assembled in the next few days. The throttle linkage would be the next challenge, but I have a couple different options in mind.
The carb comes with an electrically activated choke assembly. A number of set ups I've seen remove the electric choke activation module due to clearance issues...some running without a choke control. I'll figure that out as I go.....We'll see how the bike starts without a choke and go from there. The Weber carb uses an accelerator pump so fuel enrichment can be acheived by a twist of the throttle.
One problem I've read about is a "Hydro-lock" situation, where the cylinders flood with fuel, locking the engine. Every instance of this scenario has been due to someone leaving the fuel tank petcocks open and fuel leaking past the needle valve, effectively flooding the engine. I habitually close petcocks when engines shut down so this should not be an issue for me.
Total investment in the assembly is currently @ $300.00.

Tuesday, November 18, 2014

Mecca Beach / Sand Storm

We made a quick run over to the Salton Sea / Mecca Beach on Saturday. Since I was riding the solo /5 BMW, Darian followed up in her "chase" car. Was easy to throw all the camping gear in the trunk, rather than pack a bike.
We joined up with a few dozen fellow "Airheads" who were attending the yearly event. Great to see friends and catch up on "BS". We attended the same campout back in 2008, that was the last time we were in the area for the gathering.
 The old /5 ran without a hitch and worked well. Used 2.8 gallons to achieve the 130 miles to Niland CA.The "new" bar backs I installed made for a much better riding position. Also the small "S" Style fairing made for less wind blast on my chest.

 The Mecca Beach camping area is nice. Lots of sandy beach to set up on if one wishes. We set up across the lot next to a picnic table. A lot of close friends showed up. B. Jan Hoffman, the Airheads founder, was in attendance. B. Jan is always a "hoot" to camp with. He has always been a gracious guy and always has some good stories to tell.

A typical Salton Sea sunset. Numerous waterfowl always around. I was awoken by a massive wind in the night. At one point it was completely still outside but I could hear the roar of the wind approaching. When it arrived it was ferocious.  The large tent we were using has an 8' height so it was a good test for its' endurance. It fared well, only pulled up a couple side pegs while dancing in the wind. Packing up the tent in the 40+ MPH wind was a chore...eventually I chose to roughly roll it up and stuff it in the car trunk ...and deal with properly storing it when we got home in less windy conditions.
 Part of the ride home was with a tail wind, but turning east/west brought me into a "crosswind" which was massive. Approaching the Glamis Dunes I expected some blowing sand...but what was found was much more than that. Topping a hill, I saw a Ca. Highway Patrol car sitting with the lights flashing. I slowed down and came across a 8" sand drift across the road, probably 80 feet long. Plowing through the sand was a bit squirrely. Passing through that drift I then encountered numerous more on the road.
                                           Beautiful Downtown Calipatria CA.


 The blowing sand was brutal.....unfortunately I had my 3/4 helmet on so got a face full of sand along the way. Meeting RV's was another experience. Some of the morons were traveling at 50+ MPH and plowing into the drifts on the road. I met a couple at a "drift" and was pelted mercilessly by the flying sand.
Luckily the "dunes" area is only about 10 miles long. After passing the dunes area, the crosswinds were the next challenge. Leaning a 30* or so to keep upright. All in all there were no problems but by the time we arrived home I was worn out....the longest 150 mile ride in recent memory. Part of the Adventure!
The "lightness" of the R75/5 is not an asset in high crosswinds. My old Gold Wing would have fared much better in the wind, but not too well crossing the sand drifts in the road.

Friday, November 14, 2014

Arizona Sunshine...Mecca Beach or Bust

 Spent some time today and installed the "Emgo" S-Type Fairing. Planning on riding to the Salton Sea tomorrow for an Airhead gathering. Also installed the old "Bar Backs" I had purchased last summer. The Bar Backs were missing the top clamp....and the original /5 top clamp wouldn't work with the :stud" arrangement they use. A trip to the hardware store and the bolts needed were found.
 Euro Bar Fitment...a bit low for my crippled back. I think the repositioning of the bars will save me some back agony. Off for a couple hundred mile run tomorrow morning. Time / miles will tell.



Bar Backs rendered the friction damper unusable, but I only used it when parking anyway. Also installed a cheapo after market "S" Type Fairing. Should keep a bit of the wind off me. 


Emgo Viper Fairing 70-52501


The "bar backs" didn't come with the top clamps. Found a pair of "K-Bike" clamps for $10.00 on Fleabay. Wasn't sure if they would fit, but they fit just fine. 

Wednesday, November 12, 2014

Sub Zero Winter in November

The past week I've been closely following the weather forecast while working 13 - 14 hr. days. Initially the forecast showed a three day "cool down" with temperatures in the teens. The outlook degraded on a daily basis over the next week. When forecasts started showing temps. in the near "zero" mark it was time to go. We hurriedly prepared for departure last Friday evening and with all our earthly possessions were heading South on Sat. afternoon. Currently we are sitting South of Las Vegas NV with temps. in the 70's. Billings is now at minus 4* with minus 25* wind chill factors. Tonight the Billings forecast is for minus 10*.
Yuma AZ. is in the low 80*'s...we'll be there this afternoon. RV's and subzero weather do not go well together. I know from experience....We've been "chased" South by Weather numerous times in the past. Hated to leave work on such a short notice, but luckily I work for people who understand.

A Airhead gathering is scheduled for Mecca Beach, along the Salton Sea this weekend. Maybe we'll attend to see all our friends. The Airhead Community suffered a tterrible loss last week with the sudden death of one of the active So. Cal. members. Steven VanTwuyver passed away in his sleep a few nights ago. He was a good friend and we've spent many, many weekends camping with him over the years. I rode to Death Valley with him and another friend a couple years ago. It is hard to accept such a sudden loss of such a close friend....

Gila Mtns.

Gila Mtns.