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eonan
02.06.2006, 07:19 PM
Well I had the first test ride today. I was a tad apprehensive to be honest, as there were so many things I’ve changed, replaced, taken out etc…so many things that could go wrong! In fact the frame, the engine and the forks are the only original parts left. So…the weeping fork seal was probably the least of my worries ay! And I seemed to have a hell of a lot of nuts and bolts and bits and pieces left over too :scratchhead:

Anyway, turned out everything worked just fine. The only noticeable thing was the idling at traffic lights...it was sitting at about 3000! A little blip of the throttle would sometimes bring it back down to 1200/1300. Any ideas?

Next winter I’ll get the frame powder coated, upgrade the forks and I’m always on the look out for a 900 lump. For now though, here she is…

December...
http://i59.photobucket.com/albums/g315/eonan/before.jpg

And this afternoon...
http://i59.photobucket.com/albums/g315/eonan/after.jpg

Spud Raver
02.06.2006, 07:31 PM
Looking good. Anice gloss black frame should set her of nicely! :D

Like this........

Steve748
02.06.2006, 07:56 PM
Screwy has nicked yer mudguard!;)

Screwy
02.06.2006, 08:03 PM
Screwy has nicked yer mudguard!;)



ffs keep quite man , I could well do without a visit from the tartan mafia :eek:






:D :D :D :D :D :D :D

eonan
02.06.2006, 08:06 PM
Don't talk to me about feckin mud guards :p Do you think I can find one I like? I've tried every single one there is (really!) and I hate them all :mad:

The only one I've seen that manages to retain some of the street fighter look, is the one on the new Hypermotard...about it's only redeeming feature to be honest.

rockjock620
02.06.2006, 11:41 PM
does the next sign read "Main Road"?

Tam
03.06.2006, 05:45 AM
Well I had the first test ride today. I was a tad apprehensive to be honest, as there were so many things I’ve changed, replaced, taken out etc…so many things that could go wrong! In fact the frame, the engine and the forks are the only original parts left. So…the weeping fork seal was probably the least of my worries ay! And I seemed to have a hell of a lot of nuts and bolts and bits and pieces left over too :scratchhead:

Anyway, turned out everything worked just fine. The only noticeable thing was the idling at traffic lights...it was sitting at about 3000! A little blip of the throttle would sometimes bring it back down to 1200/1300. Any ideas?

Next winter I’ll get the frame powder coated, upgrade the forks and I’m always on the look out for a 900 lump. For now though, here she is…

December...
http://i59.photobucket.com/albums/g315/eonan/before.jpg

And this afternoon...
http://i59.photobucket.com/albums/g315/eonan/after.jpg

Looks really smart mate.
Think a nice carbon front guard would set it off and a couple of carbon air scoups, followed by a nice chrome oil cooler guard:D :D
Only jockin;)
I'de go along with a nice silk black frame paint job though.
Was it originally a gold frame cause i thought about doin my frame and rims in gold once i've got here back on the road and saved up again.:thumbs:

eonan
03.06.2006, 07:27 AM
does the next sign read "Main Road"?

:D heh heh...it is an all...clever eh!

Tam yep, that gold frame is the original colour...a nice satin black is probably the way to go :thumbs:

Any ideas about the idling problem anyone?

gordj65
03.06.2006, 08:23 AM
any chance your cold starter/choke cable is sticking just a wee bit?

eonan
03.06.2006, 08:54 AM
I changed the carbs to 41mm FCR's, so there's no choke as such, just an adjuster that allows you to set the idle (sorry if thats what you meant :o).

So when I set off, the thing is already set to idle at 1200/1300. Hmm...actually just thinking about it, maybe the throttle isn't snapping fully back...maybe the cables are sticking somewhere?

Screwy
03.06.2006, 04:29 PM
Not the grip rubbing on the switch gear is it ? Had this happen on my superlight .

eonan
03.06.2006, 04:37 PM
Not the grip rubbing on the switch gear is it ? Had this happen on my superlight .

Just been out again today, and its definately not the grip or the throttle. It seems pretty intermitant too :scratchhead:

ProjectImola004
03.06.2006, 05:56 PM
Have you adjusted the air screws on the carbs, sounds like they are way out if it's holding its revs.

They're bloody large carbs for a 750. Must be very peaky!

eonan
03.06.2006, 10:14 PM
Have you adjusted the air screws on the carbs, sounds like they are way out if it's holding its revs.

They're bloody large carbs for a 750. Must be very peaky!

The carbs were pre set by Chris at CA Cycleworks, I just slotted them in. Hmmm, you've got me a little worried now. I know that the 750 is recommended to get the 39mm, and the 900 the 41's, but the long term plan was to put a 900 engine in there, so we went for the 41's.

It is a long term plan though! Is running 41mm carbs on a 750 a bad thing then? Am I going to do any damage?

I only started riding about 6 months ago, so as yet I'm pretty unsure of the language and terminology, sorry :o "Peaky"? If you tell me what you mean by that, I'll compare it to how she feels when riding her.


I'd really appreciate any advice :thumbs:

ProjectImola004
04.06.2006, 07:47 AM
I didn't mean to sound patronising - Peaky means most or all the power is made at the top end of the rev range. 750s rev alot higher than the 900 which tops out at about 7000odd rpm. I used to run 40mm Dellorto carbs. on the 750 Santamonica but this engine had a set of race cams with very high lift (allowed more fuel to flow), long duration (stayed open for longer) and massive valve overlap (both intact & exhaust open at the same time). Coupled with a completely straight through race exhaust they carbs worked brilliantly. However the result was a very topendy (peaky) engine that drank like a fish!!!
You won't do any damage really, my only concern would be over fuelling and a possible loss of midrange torque. Those carbs run accelerator pumps which can cause 'bore washing' if playing with the throttle when the engine's not running - this is a no no.

I may have opened a can of worms here as there are many schools of thought on this subject. From my own experience of air cooled Ducs though, for normal road use, with the fitting of larger carbs; the net effect is more prominent on your wallet than real time performance on the road.

(...here talks a guy that rode a 600cc Ducati racebike with 41.5mm Malossi carbs!!!)

eonan
04.06.2006, 08:45 AM
I didn't mean to sound patronising - Peaky means most or all the power is made at the top end of the rev range. 750s rev alot higher than the 900 which tops out at about 7000odd rpm. I used to run 40mm Dellorto carbs. on the 750 Santamonica but this engine had a set of race cams with very high lift (allowed more fuel to flow), long duration (stayed open for longer) and massive valve overlap (both intact & exhaust open at the same time). Coupled with a completely straight through race exhaust they carbs worked brilliantly. However the result was a very topendy (peaky) engine that drank like a fish!!!
You won't do any damage really, my only concern would be over fuelling and a possible loss of midrange torque. Those carbs run accelerator pumps which can cause 'bore washing' if playing with the throttle when the engine's not running - this is a no no.

I may have opened a can of worms here as there are many schools of thought on this subject. From my own experience of air cooled Ducs though, for normal road use, with the fitting of larger carbs; the net effect is more prominent on your wallet than real time performance on the road.

(...here talks a guy that rode a 600cc Ducati racebike with 41.5mm Malossi carbs!!!)

You didn’t sound patronising at all…I’m the newbie here so it’s my responsibility to ask and catch up. Thanks for a great explanation.

It’s difficult for me to know whether my bike is running the way it should be or not. This is my first bike (apart from a while on a 125), and so I’ve nothing to compare it to…certainly not another perfectly running 750 to use as a base line.

I’d love someone who knew what they were doing to have a go and test it. It’s going to Ducati Glasgow on the 22nd for a new fork seal, compression testing, valve clearances etc…hopefully they might be able to test it out properly.

The things I’ve noticed so far though are:

1. She tops out at about 7500 revs
2. The biggest torque is felt when in 5th going upwards from 60mph
3. When stopping at traffic light she idles at 3000/3200 revs for 3 to 4 seconds before falling to 1200/1300

Oh…I changed the front sprocket from 15T to 14T

Update: Just had some feedback from a few folks on the UMMOC, who say they experience exactly the same thing...high idling for a couple of seconds (one guy reported up to 10!), before falling down to normal.

May well be just another of those Monster quirks god bless em :D

ProjectImola004
04.06.2006, 11:13 AM
You should be able to happily rev it to 10,000.

Holding it's revs then dropping is definately idle circuit adjustment issue.
Its definately not a Monster quirk!

Ducati Glasgow should sort you out.
Nice agressive looking bike though I forgot to say!! :)
I reckon you should put the Monster mudguard back on in the same colour as the bike, but paint the 'struts' that hold it on the forks black (like the original prototype Monster - all those years ago)!

eonan
20.06.2006, 12:53 PM
Well after studying the literature by Chris (CA Cycleworks) on ducatitech, reading Patrick Burn's excellent FCR tuning manual for the 500th time, fine tuning the fuel screws and comparing our FCR's base settings with those of a M750 with 39mm FCR's recently tuned by racer and tuner J.D. Hord (who very kindly shared the settings with me)...it looks almost certain that the problem is being caused by our slow jets being too rich.

It's going to take time and some messing around to swap in new smaller jets, fit it all back together again and re-test until we get it right, but I'm kind of enjoying all of this in a masochistic way. They came with a size 60, so I've ordered up some 58's, 55's and some 52's.

I'll let you know how we get on :comp2: :thumbs:

rockjock620
20.06.2006, 01:11 PM
the easiest solution as far as I reckon is to take it to a good rolling road man and get it properly sorted. The results are instantaneous and worth every penny, it will save you hours of time, which are better spent riding. Looks are only secondary, get the thing running!

eonan
20.06.2006, 02:41 PM
the easiest solution as far as I reckon is to take it to a good rolling road man and get it properly sorted. The results are instantaneous and worth every penny, it will save you hours of time, which are better spent riding. Looks are only secondary, get the thing running!

rockjock we did, she was on the dyno last week...just look at that sweet curve :thumbs: Like I say the only issue is the hanging revs...nowt he can do about that other than try what I've mentioned above.

Derek
20.06.2006, 03:54 PM
rockjock we did, she was on the dyno last week...just look at that sweet curve :thumbs: Like I say the only issue is the hanging revs...nowt he can do about that other than try what I've mentioned above.
I suppose 68bhp is not bad for a carb 750 although I'd have thought it would have pulled a bit more revs than that. Are you still using the standard manifolds?
The revs hanging on idle is due to too lean an idle mixture.

eonan
20.06.2006, 04:09 PM
I suppose 68bhp is not bad for a carb 750 although I'd have thought it would have pulled a bit more revs than that. Are you still using the standard manifolds?
The revs hanging on idle is due to too lean an idle mixture.

He asked me where I thought the red line was...he said he'd never blown an engine yet and didn't want to start now. Really nice bloke actually. Anyway, I've been finding the power to be falling away at around 8500, so he said he'd take her up to 8000. He did say that she just wanted to keep going though, so maybe there is more in there?

Yep same intake manifolds.

Well at first we thought it was because it was too lean, but it turns out that too rich gives very similar characteristics. The FCR gurus seem pretty certain the slow jets are running too rich.

ProjectImola004
20.06.2006, 04:54 PM
eonan,

how old is your bike? I ask this coz I know that some 750 Monsters were fitted with really soft 600 cams and small valves. (basically 600 heads) These just weren't designed for high reving, more for low down torque. You could fit a set of High lift, long duration 'G' cams fitted to the Montjuich/Laguna Sec/Santamonica 750s. I know they can still be got and slot straight in (with re-shimming of cause). Your engine would then make power upto and beyond 10500rpm - and be around the 85hp mark (which is what my Santamonica made). They would go very well with your FCRs

...food for thought

eonan
20.06.2006, 06:19 PM
eonan,

how old is your bike? I ask this coz I know that some 750 Monsters were fitted with really soft 600 cams and small valves. (basically 600 heads) These just weren't designed for high reving, more for low down torque. You could fit a set of High lift, long duration 'G' cams fitted to the Montjuich/Laguna Sec/Santamonica 750s. I know they can still be got and slot straight in (with re-shimming of cause). Your engine would then make power upto and beyond 10500rpm - and be around the 85hp mark (which is what my Santamonica made). They would go very well with your FCRs

...food for thought

Oh my good god...should I really be feeling as excited as I do right now from reading that? :scratchhead: :D

My bike is a '98, but I discovered last week that there were two versions of the '98 750, one was actually a '97. Mine is the '97.

Are they still available new, or is it an eBay thing? I know Ducati do a set of high comp pistons for this bike, but I'm guessing they'll have nothing on what you're talking about?

eonan
20.06.2006, 07:32 PM
ProjectImola you tease! Come on come on, tell me more :D

Derek
21.06.2006, 07:56 AM
eonan,

how old is your bike? I ask this coz I know that some 750 Monsters were fitted with really soft 600 cams and small valves. (basically 600 heads) These just weren't designed for high reving, more for low down torque... I know that 900 Monsters around '97 had small valve heads (750) but I didn't know that the 750s had 600 heads fitted. If I rememember right the small valve heads had a "W" stamped on them.