Author Topic: Benelli 750 SEI  (Read 5827 times)

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Offline BenelliSEI

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Re: Benelli 750 SEI
« Reply #25 on: August 23, 2022, 05:34:30 AM »
VIDEO or it doesn’t run!!!!!

Not for a while. We are heading off for a few weeks (another cycling trip, not planned by me!). The Concourse is mid September, so probably then.

P.S. it doesn’t just run, it howls!
« Last Edit: August 23, 2022, 08:28:22 AM by BenelliSEI »

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Re: Benelli 750 SEI
« Reply #26 on: August 23, 2022, 08:02:52 AM »
I don't get into may insects here most of the time.
When I lived in Florida it was crazy, they have something called "love bugs" and certain times of the year they would block your vision after a short run. Gross
1973 CB 750 K3
10/72 build Z1 Kawasaki

Offline Stev-o

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Re: Benelli 750 SEI
« Reply #27 on: August 23, 2022, 08:59:03 AM »
Check out UTube, there are a few there.

Yes, it sounds great.

'74 "Big Bang" Honda 750K [836].....'76 Honda 550F.....K3 Park Racer!......and a Bomber!............plus plus plus.........

Offline Kelly E

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Re: Benelli 750 SEI
« Reply #28 on: August 23, 2022, 09:51:11 AM »
A few rev ups doesn't cut it for me. I would like to hear it at speed. 8)
Never Give Up - Never Surrender

The Rust Bros. Garage Collection
1974 Honda CB 550 K0                                            1971 MGB/GT
1975 Honda CB 400F Super Sport                          1972 MGB/GT
1977 Kawasaki KZ 1000 LTD                                   1985 GMC S15
1978 Kawasaki KL 250
1980 Suzuki GS 1100E
1982 Honda CB 900F Super Sport
1983 Honda CB 1100F
1984 Honda VF 700S Sabre
1984 Honda VF 1000F Interceptor
1990 Moto Guzzi 1000 Le Mans
1994 Kawasaki Concours ZG 1000A9
2005 Harley Davidson Fat Boy

Offline PeWe

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Re: Benelli 750 SEI
« Reply #29 on: August 23, 2022, 10:31:45 AM »
A really special bike.
6 pipes look fantastic from behind and from each side.
Something for Honda CBX1000.

Ride a bike like that for a 200km ride and clean all insects afterwards. Butterflies and bigger dragon flies make a mess.
Plus all irritating small flying things.
CB750 K6-76  970cc (Earlier 1005cc JMR Billet block on the shelf waiting for a comeback)
CB750 K2-75 Parts assembled to a stock K2

Updates of the CB750 K6 -1976
http://forums.sohc4.net/index.php/topic,180468.msg2092136.html#msg2092136
The billet block build thread
http://forums.sohc4.net/index.php/topic,49438.msg1863571.html#msg1863571
CB750 K2 -1975  build thread
http://forums.sohc4.net/index.php/topic,168243.msg1948381.html#msg1948381
K2 engine build thread. For a complete CB750 -75
http://forums.sohc4.net/index.php/topic,180088.msg2088008.html#msg2088008
Carb jetting, a long story Mikuni TMR32
http://forums.sohc4.net/index.php/topic,179479.msg2104967.html#msg2104967

Offline Kevin D

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Re: Benelli 750 SEI
« Reply #30 on: August 23, 2022, 06:52:34 PM »
Quote
Got into it today. The Boranni rims and stainless spokes are lovely, but what a pain to clean and polish! I also had to spend some time rerouting the wire and harness to the electronic ignition control box. Managed to hide it under the battery box. Most judges deduct points for non- standard modifications. If nobody asks, I won’t be pointing at it! Pulled the inner and rear fenders too. Only way to really get them tidy and they come away easily. This “prep” may take a few days, but it’s been a while since I worked on a non-cb750. Pleasant.

Slowly working, end to end. Despite regular washing and polishing, 1200 miles has packed a bit of grime into the corners. When first fitted (2018), I spent a few afternoons getting the 6-6 Busso pipes to hang fairly symmetrically. Today I discovered the bottom two pipes, left side, were grinding on each other, for about a six inch strip. Pulled them off, polished out the damage (only visible to me!) and reset. A few shim washers and I may have got it right this time…..


Started it up this morning. First I pulled the plugs, squirted in some SeaFoam and spun up oil pressure. Cleaned the plugs and used my remote bottle to supply fuel. When I stored it away, I removed the float bowls, dried and cleaned everything, and blew out the Jets.... loaded up with fuel (no drips), and hit the button. Fired instantly, ran perfectly! I totally attribute this to the fantastic electronic ignition system I installed a while back. The triple points set up (in the same space a cb550 has two sets) were a royal pain, and never stayed were I set them. This system is brilliant.

I did put over 1200 miles on this bike, so although it looks great, definitely not “Concourse ready”.....
Clean up starts next.


John, you are one meticulous guy, and it will pay off when the judging begins. Go get ‘em. ;)
« Last Edit: August 23, 2022, 06:56:12 PM by Kevin D »
71 CB750 K1
104,000 miles
Original Owner
———past———
70 SL100/125/150
70 Candy BlueGreen CB 750 K0
————————————————-
Former Honda parts kid/counter kid/do all
—————————————————————-
Whether you think you can or think you can’t, you’re right
Genius is 99% perspiration, 1% inspiration

Offline BenelliSEI

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Re: Benelli 750 SEI
« Reply #31 on: August 24, 2022, 05:14:07 AM »
Check out UTube, there are a few there.

Yes, it sounds great.


Steve...... That’s the best video out there and the last few minutes sound just right! The master cylinder and bar end switches have been substituted with later Moto Guzzi units. The original switches are incredibly fragile, and the wiring harness was marginal when new! I came really close to replacing the wiring harness, all ignition parts and switches with replica cb750 parts!

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Re: Benelli 750 SEI
« Reply #32 on: August 24, 2022, 07:59:32 AM »
Wow doesn't even start to express how cool that is.
The exhaust is great, at idle the muffled popping almost has a two stroke sound.
I wonder how much power it makes?

Best of luck
1973 CB 750 K3
10/72 build Z1 Kawasaki

Offline BenelliSEI

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Re: Benelli 750 SEI
« Reply #33 on: August 24, 2022, 10:06:35 AM »
Wow doesn't even start to express how cool that is.
The exhaust is great, at idle the muffled popping almost has a two stroke sound.
I wonder how much power it makes?

Best of luck

Depends what you read! 58-71 bhp!

Offline simon#42

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Re: Benelli 750 SEI
« Reply #34 on: August 24, 2022, 10:06:45 AM »
i would guess it makes the same as one and a half cb500s as that is what it is .   nice bike though .

Offline BenelliSEI

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Re: Benelli 750 SEI
« Reply #35 on: August 24, 2022, 10:29:36 AM »
i would guess it makes the same as one and a half cb500s as that is what it is .   nice bike though .

No question where the “inspiration” came from! If you look at a Benelli 500 Quattro (4 cylinder/ 4 carb engine) it looks identical to a cb500. I’ve seen a Quattro with a cb550K motor installed, and it appeared to be a bolt in swap......

The SEI has way more Benelli design features, but still lots of similarities. The most amusing is the “deep sump conversion” that many owners have done, including me. The sump comes from a cb650, and bolts on with no modifications!

Offline BenelliSEI

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Re: Benelli 750 SEI
« Reply #36 on: August 24, 2022, 10:31:50 AM »
Getting there. Bike is prepped from the horn back. Front end when we return in a few weeks.....

Offline PeWe

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Re: Benelli 750 SEI
« Reply #37 on: August 24, 2022, 11:29:30 AM »
58 vs 71 can be same power.
On the wheel vs crank hp.

That is a very special bike that must be saved for future generations to admire.

CB750 K6-76  970cc (Earlier 1005cc JMR Billet block on the shelf waiting for a comeback)
CB750 K2-75 Parts assembled to a stock K2

Updates of the CB750 K6 -1976
http://forums.sohc4.net/index.php/topic,180468.msg2092136.html#msg2092136
The billet block build thread
http://forums.sohc4.net/index.php/topic,49438.msg1863571.html#msg1863571
CB750 K2 -1975  build thread
http://forums.sohc4.net/index.php/topic,168243.msg1948381.html#msg1948381
K2 engine build thread. For a complete CB750 -75
http://forums.sohc4.net/index.php/topic,180088.msg2088008.html#msg2088008
Carb jetting, a long story Mikuni TMR32
http://forums.sohc4.net/index.php/topic,179479.msg2104967.html#msg2104967

Offline Magpie

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Re: Benelli 750 SEI
« Reply #38 on: August 24, 2022, 05:49:33 PM »
Beauty! Cliff.

Offline BenelliSEI

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Re: Benelli 750 SEI
« Reply #39 on: August 25, 2022, 05:05:08 AM »
Beauty! Cliff.

Thanks Cliff! It is a special motorcycle, pretty rare in Canada, I know of only two others. My concern is that like my K0 that went to the 2019 Cobble Beach event, it’s too clean/special to actually use regularly. I have a K1 and K3 we ride all the time, so these bikes eventually just sit. I did sell the K0, but my other two projects (Sandcast and Rickman CR) are headed the same way…… Mmmm. No complaints, good “problem” to have.
« Last Edit: August 25, 2022, 05:13:40 AM by BenelliSEI »

Offline Stev-o

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Re: Benelli 750 SEI
« Reply #40 on: August 25, 2022, 06:27:41 AM »
Beauty! Cliff.
Mmmm. No complaints, good “problem” to have.

We call that a "First World Problem"!!
'74 "Big Bang" Honda 750K [836].....'76 Honda 550F.....K3 Park Racer!......and a Bomber!............plus plus plus.........

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Re: Benelli 750 SEI
« Reply #41 on: August 25, 2022, 08:03:45 AM »
Yes indeed, first world.
Cool the way they put the alternator behind the cylinders, I don't think many were like that back then. I know the CBX was like that.

I am very envious of your shop, what fun.

1973 CB 750 K3
10/72 build Z1 Kawasaki

Offline simon#42

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Re: Benelli 750 SEI
« Reply #42 on: August 25, 2022, 11:14:14 AM »
Beauty! Cliff.
Mmmm. No complaints, good “problem” to have.

We call that a "First World Problem"!!

a problem i have never experienced !

Offline BenelliSEI

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Re: Benelli 750 SEI
« Reply #43 on: August 25, 2022, 01:19:07 PM »
Beauty! Cliff.
Mmmm. No complaints, good “problem” to have.

We call that a "First World Problem"!!

a problem i have never experienced !

Like I said: good problem to have…….

Offline Flyin900

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Re: Benelli 750 SEI
« Reply #44 on: August 27, 2022, 06:22:05 PM »
Hey John, I don't know if you know Steve Troop of CVMG Headwaters based out of Penetanguishene. He has over 25 vintage Italian only bikes of every possible variety and model.
 
They are all licenced and insured and he rides each one on a rotating basis which is something to see. He normally joins our Wednesday rides, where it is such a treat to see him arrive on a different model each week.

I have seen your work and do wish you best of luck, as I am sure the Benelli will be up to your usual fine work with fit and finish.
« Last Edit: August 27, 2022, 06:23:53 PM by Flyin900 »
Common sense.....isn't so common!

1966 CL77 - 305cc - Gentleman's Scrambler
1967 CL175K0 - Scrambler #802 engine
1972 CB350F - Candy Bacchus Olive - Super Sport
1973 CB350F - Flake Matador Red - Super Sport
1975 CB400F - Parakeet Yellow - Super Sport
1976 CB400F - Varnish Blue - Super Sport
1976 GL1000 - Goldwing Standard
1978 CB550K - Super Sport
1981 GL1100 - Goldwing Standard
1982 CM450A - Hondamatic
1982 CB900C - Custom
1983 CX650E - Eurosport
1983 CB1000C - Custom X 2 Bikes now - both restored
1983 CB1100F - Super Sport - Pristine example
1984 GL1200 - Goldwing Standard

Offline BenelliSEI

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Re: Benelli 750 SEI
« Reply #45 on: August 27, 2022, 11:43:53 PM »
Hey John, I don't know if you know Steve Troop of CVMG Headwaters based out of Penetanguishene. He has over 25 vintage Italian only bikes of every possible variety and model.
 
They are all licenced and insured and he rides each one on a rotating basis which is something to see. He normally joins our Wednesday rides, where it is such a treat to see him arrive on a different model each week.

I have seen your work and do wish you best of luck, as I am sure the Benelli will be up to your usual fine work with fit and finish.

I do know Steve. He does have an amazing collection! His SEI is beautifully restored (by another CVMG Member). Cheers, John D.

Offline newday777

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Re: Benelli 750 SEI
« Reply #46 on: August 28, 2022, 03:31:37 AM »
One ride can cause lots of cleaning.
Insects, my bikes are full of them, my K6 that frequently get a +200km ride has lots of dried kamikaze insects.

I need to lay wet cloths on bike to make the dried glued insects softer a d easier to remove.
They fill all areas..... My helmet too.

Soak the rags with hydrogen peroxide. That eats the bugs and doesn't damage the paint.
Stu
Honda Parts manager in the mid 1970s Nashua Honda
My current rides
1975 K5 Planet Blue my summer ride, it was a friend's bike I worked with at the Honda shop in 76, lots of fun to be on it again
1976 K6 Anteres Red rebuilding project, was originally my brother's that I set up from the crate, it'll breath again soon!
Project 750s, 2 K4, 2 K6, 1 K8
2008 GL1800 my daily ride and cross country runner

Prior bikes....
1972 Suzuki GT380 I had charge of it for a year in 1973 while my friend was deployed and learned to love street riding....
New CB450 K7 after my friend returned...
New CB750 K5 Planet Blue, demise by ex cousin in law at 9,000 miles...
New CB750 K6 Anteres Red, to replace the totaled K5, I sold this K6 at 45k in 1983, I had heavily modified it, many great memories on it and have missed it greatly.....
1983 GL1100A, 1999 GL1500 SE, 1999 GL1500A

Offline BenelliSEI

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Re: Benelli 750 SEI
« Reply #47 on: September 12, 2022, 02:04:01 PM »
Finished detailing the Benelli today. The Concours is this weekend. Foul, foggy and rain all day! Pictures next sunshine!

Offline grcamna2

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Re: Benelli 750 SEI
« Reply #48 on: September 12, 2022, 05:37:16 PM »
One ride can cause lots of cleaning.
Insects, my bikes are full of them, my K6 that frequently get a +200km ride has lots of dried kamikaze insects.

I need to lay wet cloths on bike to make the dried glued insects softer a d easier to remove.
They fill all areas..... My helmet too.

Soak the rags with hydrogen peroxide. That eats the bugs and doesn't damage the paint.

Stu,can I use the Hydrogen Peroxide on plastics also? I'm thinking of my helmet & facesheild
« Last Edit: September 12, 2022, 06:26:35 PM by grcamna2 »
75' CB400F/'bunch o' parts' & 81' CB125S modded to a 'CB200S'
  I love the small ones too !
Do your BEST...nobody can take that away from you.

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Re: Benelli 750 SEI
« Reply #49 on: September 12, 2022, 06:19:05 PM »
You can use hydrogen peroxide for lots of stuff, even pour the over the counter stuff on a cut to clean it.
1973 CB 750 K3
10/72 build Z1 Kawasaki