Hi all, whilst checking over a newly bought 998s FE, I noticed what appears to be a missing fastener on the carbon fibre belly pan. Specifically, at the rear of the belly pan on the left hand side there is a moulded-in vertical tab provided with a plain hole which seems to align with a hole at the back of the crankcase. On my bike this tab is not secured against the crankcase since no fastener is present. My question is: what type/size of fastener should be installed in this position? Thanks for your help in advance.
Hi, thanks for the fast reply. The belly pan tab looks fine and aligns with the hole in the crankcase, its just that I don't know what type of fastener is used in this position (I am assuming that the tab is supposed to be positively located since the hole in the tab is concentric with the hole in the crankcase?). I snuck a look at an installation on another 998s FE in the auction at the Classic Bike show yesterday. The vertical tab looked the same as mine and it was secured with a small dome head screw and oversize washer concentric with the hole in the crankcase - didn't look original though. Sorry can't do a photo at the moment (v.bad back - not Ducati related....).
Yes, there should be a fastner there to secure the belly pan to the frame. From memory it’s a screw as opposed to a Dzus type fastner but I’ll have a look on my 998S and report back.
you maybe missing the small insert that fits inside the engine casing- 71040021A this reduces the size to enable you to use a smaller screw
It depends on which type of belly pan it is. There were at least 3 different versions. If yours is the one with the spout thing on, it just goes inside the lower crankcase hole. One of the versions had no fixing point on it at all and tbh, this is probably the best one. My 998S had the spout thing on but my 996R one has nothing. Makes no difference…
Thank you all for the feedback. I didn't know bout the crankcase insert - when my back allows, I will double check this area. When I first noticed the missing fastener, I did have a poke around inside the crankcase hole and could feel some sort of step-down shoulder but it didn't occur to me that it may be a threaded insert - I hope it is ! I also didn't realise there were different types of CF belly pans. Thanks again for all your help help.
This is how the belly pan is fixed on my 998S . I'm about to leave for work so haven’t got time to remove side fairing to unscrew bolt to check size, but I can later if you like.
Thanks for posting the photo - the CF Belly Pan fixing tab looks the same as mine but I had no screw fitted. However, I now understand what has happened (I think). Just inside the crankcase hole facing there is what appears to be a short length of very thin wall copper tube - I assume this was some sort of codge by a previous owner because behind this tube floating loosely around inside the casting was the previously mentioned threaded insert - I just pushed this out through the opposite side of the crankcase with a small magnet. The insert is threaded M6 and I guess was originally a press fit in the crankcase hole. I assume it had got displaced at some time in the past and was just left inside the casting. I can't easily re-fit this insert so, for now as least, I plan on installing a long length of M6 allthread bar and clamp up with a nut at both ends (so another codge then!). Thanks again for everyone's help.
I bought the threaded insert, however, it is a very tight fit that I don't think it will go in properly if I just try to hammer it in. Do any of you have ideas on how Ducati press fit this threaded insert into the crankcase hole? Because if they use press, the upper wall of the threaded insert might collapse since it is only made of thin zinc plated steel material. Even the lower part where it has the M6 thread is already larger than the hole in the crankshaft, let alone the upper part which is even wider but also has thinner wall. Here is how it looks like (I took the picture from Stein Dinse website):
My guess is it is inserted using a bolt threaded into the insert. Then lightly drifted in. If it starts to mar/jam then I’d remove and do some light relieving of the insert surface . Putting the insert in the freezer before hand may help.
Since I originally started this thread, I have a bit more info to add: I actually purchased the Threaded Insert Part No. 71040021A from Ducati and it is a bit different from the one shown in the photo. The smaller diameter step has a short parallel land on the end then a slow back taper into the large diameter step (presumably to ease fitting). The M6 thread is counterbored at the thin flange/large step end, to accept the associated fixing screw. The Threaded Inset Part No. is shown in the 998S parts book whereas the 998S FE parts book doesn't appear to show this insert. Anyway, the Insert doesn't fit the associated hole in my 998S FE crankcase (the hole diameter is significantly smaller) so I would assume that the 998S crankcase is machined differently to the 998S FE crankcase in this respect (at least it is in my engine). I had assumed that they were identical, hence my purchase of the Insert............. Incidentally, my engine is the original one and is the deep sump type. Anybody got any thoughts on this ?
These are the pictures of the insert that I bought: They are Part#71040021A and looks like the original picture I copy from Stein-Dinse website. My engine is actually a Deep Sump engine from 2005 999S but I am pretty sure all 998 and 999 deep sump engine had the same size holes. I think Ducati must have pressed them with a machine press. It need to be tight otherwise, the insert will spin when tightening the M6 bolt. I might try the screw the bolt into the insert and tapping them with rubber mallet and see if I am able to force it in.
After purchasing my Insert from Ducati, I remember measuring its outside diameter and the inside diameter of the corresponding hole in my crankcase. I didn't keep a record of the actual dimensions but recall that the degree of interference meant that the Insert could not be installed. This was what prompted me to check the 998S FE parts book (after purchasing the Insert based on the 998S parts book) only to discover that the Insert does not appear to be listed for this model. Prior to this I had assumed that the 998S and 998S FE engines were identical but, going by my experience and the difference in the parts books, I concluded that they are not the same in this respect. I am no Ducati expert (I am quite good on Velocette spring frame push rod singles.......) so I'm a bit confused by it all!
I vaguely remember that the FE got different engines in different markets - some with titanium conrods and deep sump, and some not? - which wouldn't help with clarity here. Is that possible?
The 998S/996R engines are referred to as gen 1 engines. The 998FE engine was the gen 2, painted. Not sure about any differences in that crankcase hole diameter.
I note that some 998S FE engines were sand-cast and some weren't. But don't know whether that would make any difference either.
When I originally posted my question regarding the 998S FE, bettes advised that there were at least 3 different types of belly pan, one of which had a 'spout thing' moulded into the fixing tab which simply pushed into the crankcase hole (so no insert or screw required). I recall studying John Hackett's beautiful original 998R at his dealership in Coventry and this featured the 'spout thing' arrangement. Its not worth me buying another belly pan of this type to replace the one fitted to my bike (which has a plain hole in the fixing tab to accept the M6 screw and thus needs the associated threaded insert). Since the standard Ducati 998S insert wont fit into my 998S FE crankcase hole, I ended up using a home made insert together with a standard Ducati screw - I am happy with the result. Makes me wonder if Ducati simply used up whatever stock they had on the shelf when building the FE ? Mind you, even if that was the case then I still think they ended up building the most beautiful bike in the world !
