By Mark gardner
#84876
Any body know how to extend the swing arm , I have read that an interceptor swing arm fits and is 4" longer , new to the scene and not great at engineering , any help appreciated
Mark :
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By stinkwheel
#84877
First question is what model of bullet because there are a few bikes now which have been marketed as a "bullet"?

On a more personal note, I'm interested to know more about your project and why you'd want a longer swingarm on a bullet? Pure aesthetics? Of all the bikes I've ridden, I wouldn't have said a bullet is drastically unstable in terms of road holding, has twitchy handling handling or has trouble putting power down without wheelying. Those being the usual reasons I'd think of someone wanting to do this. Or are you making an awesome stretched-out hillclimber for Red Marley?

If it's for aesthetics and for road use, you will probably also need new shocks too to push the rake angle back out again or it'll flop over into corners, and stronger springs to counteract the extra leverage.

I suppose with a standard one being basically two tubes, if you can't find something to fit, it wouldn't be the worlds hardest one for a decent engineer to cut, slug and weld a bit into a standard one. Maybe with some added bracing/gusset/both because 4" longer is a fair bit.

You might struggle to find an interceptor swingarm.
By Andy C
#84878
Inclined to agree with Stinkwheel - an interceptor arm would be hard to find, and as the standard arm is a simle tubular affair any decent fabircator worth his salt shoule be able to cut / slug / weld in an extension.

Also curious as to the reasons behind extending the arm - would you like to share ?
By Mark gardner
#84885
Thanks guys , purely aesthetics , looking for a longer leaner look , 4” extension is probably in extreme , maybe only 2” and longer shocks to suit , putting the electrics in the tool boxes , seen an image on the web and liked it , I would love to hard tail it but don’t have the skills
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By PeteF
#84888
Take it to a good welder/fabricator (unless you are one) with a decent drawing of what you want.
Ideally one who understands motorcycles.
Make sure he welds a slug (or tube) inside the swing arm where it's been cut. Don't rely on a butt weld (unless he's a VERY good welder)
You will probably want to cut forward of the brake arm anchor point.
Altering the swing arm like this will alter the handling of the machine but not necessarily badly. It will just be different.
Be aware you're going to have to move the mudguard as well and probably other bits. Chain and brake rod will be longer for a start of course.
By Adrian
#84892
If you look at the frame there is another set of lugs behind and just below the swinging arm pivot, I have seen people just move the existing swinging arm back to pivot that position. Saves chopping anything about frame-wise about in case you don't actually like the look when it's done and want to put it back to standard afterwards.

The UK-built Bullets changed to a different design of frame in 1956, and the Interceptor uses a version of this with, I suspect, a wider swinging arm. I say this because I have successfully fitted Indian Bullet swinging arms into later frames, but they need extra spacers to fill up a gap either side on the swinging arm pin.

A.
By vince
#84992
Hi the interceptor swingarm is extended by lengthened axle plates if you extend the tubing your'll move the shock absorber pivot point . Our host sell longer swingarm in used parts. Vince
By singleminded
#85018
As has been mentioned. the swinging arm as fitted to UK twins is wider at the pivot point than the Indian one. Therefore it is too wide to fit the Indian Bullet frame. I suppose you could probably use a UK one if you cut a section out of the pivot tube and the reinforcement tube and weld it back together, making it the same width as the Indian one.
You would need to get the tape measure out first to see if this would work, also checking chain line and such. (measure twice, cut once, etc.)
(I'm referring to the iron engine Bullets here.)

I am actually playing around with a longer swinging arm for my 2003 Bullet. The arm is from a Yamaha XS650. The pivot point is the same width as the Indian Bullet type, so fits the frame. The wheel spindle location is 4" approx further back (hence the wheelbase is 4" longer,) but the mounting point for the bottom of the rear suspension units is further forward on the rear lugs. If you google XS650 swing arm you will see what I mean. Therefore the rear units do not need to be massively longer.

I am using a Honda CB500 wheel spindle and slightly modified XS650 chain tensioners. I had to have a longer rear sprocket bearing hollow dummy axle made up, also I've had to make-up spacers for the r/h side. The trickiest bit was welding a plate on the l/h end of the arm for the Enfield brake plate to fit.
I just need to sort out the pivot bearings and spindle - not a big job but I'm also rebuilding an Ariel Square Four, a Series 1 Interceptor and a Matchless G11...............

Why am I looking to extend the swinging arm? I'm 6' 3" and the Bullet is a bit small for me. It also looks like someone has rear-ended it and pushed the back wheel forwards! IMHO, they all look like that, including the twins before Enfield themselves lengthened the arm by fitting longer plates on the end, as discussed earlier.

With the wheel further back, I'll be able to address my other pet hate with Indian Bullets - the two carbuncles known as tool boxes or whatever. With a bit of modification, I will be able to move them both inwards so they will no longer be the widest parts of the bike!

The bike is fun to ride, however, with a Tollgate 625 engine (flowed head, 32 mm carb, forged piston, steel rod, roller big-end, sports cams etc) and a 5-speed box. I'd just like it to fit me better!

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