Hex bar length for Delorto 36s?

evernon · Post by **evernon** » Sat Mar 24, 2007 9:43 pm

I am collecting parts for a 1911 build. I need to order parts to complete the hex bar linkage for dual Delorto 36s. What length will I need for the hex bar? This will be installed with the DTM shroud. Any help would be appreciated. I could wait and measure when they are bolted on but it would be nice to have parts ready for install.

Thanks

Post by **Piledriver** » Sat Mar 24, 2007 11:53 pm

It depends on your manifolds offset...

When I bought the CB aircleaner/hexbar kit, great price... Looks nice, nice HD heim joints, castings etc...

I needed to shorten the bar ~ 1 inch. YMMV.
(easy)

BTW, I reworked my throttle linkage after ~ a month of jacking with the POS hexbar, using a motorcycle cable splitter and some simple angle iron brackets etc. Took me an hour.
(You get what you pay for?)

Worked PERFECT.
(someone should make these...)

I suggest you JUST buy the air cleaner kit, and get/make a decent throttle linkage.

(I'm pretty sure Jake sells a beautiful BB bellcrank one just for the DTM)

The CB hexbar has ... fundamental design issues that aren't really fixable IMHO.
(symptom---Accel pumps spit gas ~constantly, esp after it wears in for a few weeks)

evernon · Post by **evernon** » Sun Mar 25, 2007 6:28 pm

I don't know about the manifold offset - I assumed they were all the same. The carbs I purchased used have the filters and mounting brackets for the hex bar setup but no linkage. I would like to go with Jakes bell crank but don't have the funds right now. I think I can complete the hex bar for cheap and put the money saved into some quality pistons. Did you split and attach throttle cable to each end of the hex setup? Why was this necessary? I have never had this type of linkage before.

Thanks.

Post by **Piledriver** » Sun Mar 25, 2007 8:27 pm

No, the split cable pull eliminated the hexbar completely.

The angle iron brackets acted as stops for the pull cable sheaths. (2 bicycle brake cables)

I eventually made up 2 SS pulleys for the cables to wrap around, better small throttle opening linearity than the levers.

Lives in a box with the carbs... Went to CIS FI.
(914, tons of room)

evernon · Post by **evernon** » Tue Mar 27, 2007 7:54 pm

What are the downfalls of the hex bar setup? My sandrail will log less than 1000 miles a year but linkage will be exposed to the elements. I could see sand getting in the sheath if I were to use cables as you have described.

Post by **Piledriver** » Tue Mar 27, 2007 9:07 pm

It would be easy to seal up cables... little bellows on the end...Used on dirt bikes etc.

Lube w/graphite and they don't attract crud anyway.

(Plus the exposed bits are $5... available anywhere)

The hexbar gets sloppy quick, and it's mass/vibrations "work" the accel pumps constantly.

I push 2000 miles a month, so YMMV.

BajaPorsche · Post by **BajaPorsche** » Wed Mar 28, 2007 8:29 am

Ahhh, I've been thinking about the same type set-up Piledriver....... but only a thought........ If you have foto's, and a parts list.....Wow.... that would save alot of time, and trial and error......

The hex bar linkage is supposedly the best set-up, but like you said, it can get sloppy real fast, especially in an off road application...... a split cable is almost like a rigid application, only open to adjustment....... again, any foto's would be appreciated.

Post by **Piledriver** » Wed Mar 28, 2007 10:02 am

I'll see what I can do for pics.
(May throw up a new thread)

I have pics of the pulleys I made up... hardly required, but have some nice features.
(Adjusting the linkage is absolute cake if you have to pull a carb etc..., as the cable is clamped by a screw in the OD.. wrap around, pull tight, clamp--- further adjustment was usually not needed)

If you don't mind actually spending money, you can actually buy nice new cable splitters...

A motorcycle scrapyard will get you most everything you need for ~$20 worst case. I spent ~$5. YMMV.

On a baja, I'd run a sheathed cable all the way to the tube by the trans... Any throttle interaction due to the engine moving would be gone, and the whole setup could be sealed easy.

I might even put the splitter back there...

BajaPorsche · Post by **BajaPorsche** » Thu Mar 29, 2007 2:12 pm

splitter, I have some motorcycle parts here, but I can't picture where the splitter would go on the bike except for a dual carb from the throttle type set up........

on the dell 36's it has a sync adjustment on the carb, so setting the slack would be easy enough, but I was thinking of the thumb screw type cabl;e adjustment like on the clutch and hand brake cables.... that seems like it would be a nice syncing point too.....

if you set up another link, i'd like to see it.... I was thinking splitting inside the engine compartment......less parts exposed to the elements..... the engine compartment is an easy see/clean area.......... but by the trans..... well, I might overlook that area.

Sounds good though..... kinda like real good..... I'll look on ebay to get a look at what the cable splitter looks like.
thanks Pile for the info

Post by **Piledriver** » Thu Mar 29, 2007 10:18 pm

The splitter I'm talking about has the cable from the throttle (single) pulling on a piston, and 2 (or more) cables to the carbs go out the other side.

The cables swaged on ends lock into the piston, usually nylon or such in a nylon tube body.

A LOT of bikes had these.

You can get shmancy-fancy ones in pure billet unobtainum for HDs...

The balance adjustment from old bike carbs works~OK, but depends on if you are using those cables. I used bicycle ones.

I step drilled out a bolt to size/used a locknut.

You only need to adjust one.

If you go to the pulleys (will post pics this weekend, I promise) just loosening up the clamp screw and tugging the cables tight is very highly repeatable...

I only ever had to actually adjust the sync once... when I installed it.